View Full Version : Mefi tuners
transam
10-28-2012, 11:05 AM
Does anyone know of any good mefi tuners in washington state or even vancouver bc canada? I am stuck with a mefi equipped turn key engine with no way of tuning it. I really dont want to take the car to california if i can avoid it. Also how safe is a mefi system? Without a mass air or o2 sensors how does the ecm know if the motor is about to melt down? I know it has a knock sensor but simce it has a kenne bell supercharger im sure its sensitivity is programmed on the lower end as ive heard the harmonics of the blower can set a knock sensor off. Any help would be appreciated
camcojb
10-28-2012, 12:55 PM
If you're talking MEFI 4 I sympathize with you. I did some tuning on a car with that system, and it's very clunky to tune in my opinion.
transam
10-28-2012, 03:33 PM
I am contemplating going fast or have a custom harness made and go oem gm ecm. Im not sure which way is the better way to go at this point ,i dont know a lot about this system other then it is gm marine delphi system. Judging from the headache i have im assuming its not a desirable set up
camcojb
10-28-2012, 04:55 PM
I am contemplating going fast or have a custom harness made and go oem gm ecm. Im not sure which way is the better way to go at this point ,i dont know a lot about this system other then it is gm marine delphi system. Judging from the headache i have im assuming its not a desirable set up
I would say it is not a desirable system. The standard GM ecm's work great with either EFI Live or HP Tuners software to do the tuning.
Jody is the MEFI system "handcuffed" due to marine designation and environmental issues?
James OLC
10-28-2012, 06:50 PM
The MEFI system is handcuffed not because of its marine roots... It's just old and simple and not too many tuners are any good at tuning it (or want to learn). You can get it to work and you can run it with O2 sensors but it takes patience and a good tuner. Hunt around and try to find a tuner who can maybe come to you (ie. Mike Norris)...
camcojb
10-28-2012, 07:29 PM
Jody is the MEFI system "handcuffed" due to marine designation and environmental issues?
The MEFI system is handcuffed not because of its marine roots... It's just old and simple and not too many tuners are any good at tuning it (or want to learn). You can get it to work and you can run it with O2 sensors but it takes patience and a good tuner. Hunt around and try to find a tuner who can maybe come to you (ie. Mike Norris)...
yeah, it just doesn't have the software or tuning resolution of the modern systems or normal GM ecu's. I got some help from a GM engineer to get it to at least a point where I could tune from, and the car ran pretty good by the time I was done. I just would not recommend it based on my experience with it.
It's like most systems, if tuned properly it's capable, but this one just is a lot tougher than it needs to be to get right.
Sparks67
10-28-2012, 07:47 PM
You might be able to contact Rich Gala of UCS Tuning. http://www.ucstuning.com/ Former W2W. He can give you advice on who to contact, but on supercharged engine you want a good tuner. My Harrop TVS 2300 LS3 418 uses LS1 ECU and Speartech Harness, but it was tuned with HP tuners software.
The problem that I ran into was finding a person that can use HP tuning software, that had experience tuning a Supercharged engine, so Kurt Urban hooked me up with Rich Gala. Also, you need to find a tuner that is willing to travel to your location.
Jeff
supremeefi
10-29-2012, 05:03 AM
Yes that system is dated, batch fire (all 8 at once), and further tuning is limited. Watch my video where we replaced one with an aftermarket ECM. Went from having to use 93 and getting 10mpg to using regular and getting 15+.
With a blown application especially, I'd opt for an aftermarket system.The safeguards alone would make it worth it.
At the end of the day you'll be glad you went in another direction.
64duece
10-29-2012, 05:18 AM
I'd also agree that going to an aftermarket system is probably money and time well spent edpecially with the limited capability of that ECU. I used to tune them for years, they are a PITA. Don't bother anymore as the reults are just not worth the time invested. Check into Holley HP ECU & Harness Kit. I think you'll find the price and tunability a nice option.
Mike Norris
10-29-2012, 03:50 PM
The system itself is not that bad, but it is the actual tuning software and support that is lacking. I tuned Kyle Busch's Camaro for Detroit Speed and it was a SC'd LS engine. It took a while but actually got it pretty good.
So can it be done? Yes. It it worth the time and effort to do it? Debateable for sure. But even before it can be tuned there are a few things to find out.
Do you have the cable and USB security key? Is it already set up for a 2 bar MAP sensor for forced induction? Is it set up and wired in for wide band oxygen sensor(s)? If the answer is no to all of these, then the cost to upgrade to this point plus tuning time may well exceed the cost of going to a GM factory ECU package or any of the aftermarket kits.
Hope this helps.
Mike Norris
camcojb
10-29-2012, 03:59 PM
The system itself is not that bad, but it is the actual tuning software and support that is lacking. I tuned Kyle Busch's Camaro for Detroit Speed and it was a SC'd LS engine. It took a while but actually got it pretty good.
So can it be done? Yes. It it worth the time and effort to do it? Debateable for sure. But even before it can be tuned there are a few things to find out.
Do you have the cable and USB security key? Is it already set up for a 2 bar MAP sensor for forced induction? Is it set up and wired in for wide band oxygen sensor(s)? If the answer is no to all of these, then the cost to upgrade to this point plus tuning time may well exceed the cost of going to a GM factory ECU package or any of the aftermarket kits.
Hope this helps.
Mike Norris
thanks Mike. See you this week. :thumbsup:
transam
10-29-2012, 07:01 PM
The system itself is not that bad, but it is the actual tuning software and support that is lacking. I tuned Kyle Busch's Camaro for Detroit Speed and it was a SC'd LS engine. It took a while but actually got it pretty good.
So can it be done? Yes. It it worth the time and effort to do it? Debateable for sure. But even before it can be tuned there are a few things to find out.
Do you have the cable and USB security key? Is it already set up for a 2 bar MAP sensor for forced induction? Is it set up and wired in for wide band oxygen sensor(s)? If the answer is no to all of these, then the cost to upgrade to this point plus tuning time may well exceed the cost of going to a GM factory ECU package or any of the aftermarket kits.
Hope this helps.
Mike Norris
No usb,it has a 2 bar map,no o2s. Ive had cars with big stuff,fast and this mefi has thrown me for a loop. Thanks for the input,the consensus seems to be to throw the mefi out and go with oem .
Matt@BOS
10-29-2012, 08:21 PM
Probably a wise choice to ditch the MEFI 4. As others have said, it wont cause your engine to just spontaneously combust when you turn it over, however if there is no one in your area who knows their way around the system, that you would trust to tune the car, then it seems like a no brainer to switch it out. I know most people roll their eyes and groan when they hear I have a MEFI computer.
Matt
parsonsj
12-03-2012, 07:25 AM
The MEFI is an OEM system, and is far more capable than even modern retail aftermarket systems, with the exception of the new Holley Dominator.
Mike Norris and I were able to get the a MEFI system to work really well. We worked with the folks who used the MEFI-Burn setup, and were able to get the car to start quickly, idle nicely, get good mileage, and have good power. In value terms, they are hard to beat. You just need to find someone who can handle them, and you need to the cable and USB key to unlock them (what Mike said).
transam
12-03-2012, 08:48 PM
Being as my system doesn't use a wideband/o2 do you feel it's a good set up on a supercharged set up? I have no problem using the mefi as long as I can have it running right. I can drive the car down to California or anywhere on the west coast but then the car won't be tuned for the altitude and temps back home. It's either that or do it locally but spend 700+ for the USB and unlock. That's why I was debating throwing a fast at it that will retain my drive by cable tb and not require a maf,or run oem ECM and running a maf and drive by wire set up.
Rybar
12-04-2012, 10:56 AM
Being as my system doesn't use a wideband/o2 do you feel it's a good set up on a supercharged set up? I have no problem using the mefi as long as I can have it running right. I can drive the car down to California or anywhere on the west coast but then the car won't be tuned for the altitude and temps back home. It's either that or do it locally but spend 700+ for the USB and unlock. That's why I was debating throwing a fast at it that will retain my drive by cable tb and not require a maf,or run oem ECM and running a maf and drive by wire set up.
Paul there's a lot of Burger joints en route from here south to Cali. ;)
camcojb
12-04-2012, 12:12 PM
Being as my system doesn't use a wideband/o2 do you feel it's a good set up on a supercharged set up? I have no problem using the mefi as long as I can have it running right. I can drive the car down to California or anywhere on the west coast but then the car won't be tuned for the altitude and temps back home. It's either that or do it locally but spend 700+ for the USB and unlock. That's why I was debating throwing a fast at it that will retain my drive by cable tb and not require a maf,or run oem ECM and running a maf and drive by wire set up.
I like the wide band systems like Fast, Accel, etc. that allow wide open throttle closed loop for forced induction setups. Just gives a little motre safety factor in that the correction is still on at WOT and it will try to add fuel if you're lean or subtract if you're lean. Plus you can limit how much it adjusts either way.
With that said, the non wideband systems like the factory ECM's work fine with forced induction, with the proper tune. I am not a fan of the MEFI 4, I would never run that system in anything I owned. Just doesn't have the features and easy tuneability of most the other systems. Does it even run a two or three bar MAP?
parsonsj
12-04-2012, 02:42 PM
Just doesn't have the features and easy tuneability of most the other systems. Does it even run a two or three bar MAP?I don't know about 2 or 3 bar MAPs, but the MEFI 4b and 5 are big advances over previous MEFI systems, and even those have more capability than aftermarket systems. It's just that tuning software is lacking for them in a non-proprietary offering. If you have a MEFI, it's connected and you have a running car, and you've got the cable and USB dongle, I'd keep it. They can be connected to wideband or narrow-band O2 sensors, either one or two. They can be run closed loop at WOT. It's just that the tuner/end user has to do the integration to get it all working. If you are buying something new, I'd get something more user friendly.
transam
12-04-2012, 06:24 PM
I'm not sure if its a 2/3 bar, I'd assume it would have to be 2 bar for turn key to use it on a supercharged set up? And no I dont have the cable/dongle. Now you guys have me thinking,if they made a mistake and put a 1 bar map what would be a symptom ? It feels like its hitting a rev limiter when it gets Into load around 2000rpm
transam
12-04-2012, 06:26 PM
Paul there's a lot of Burger joints en route from here south to Cali. ;)
I've made the trip many times, and probably more bathrooms in between:lol:
camcojb
12-04-2012, 07:04 PM
I'm not sure if its a 2/3 bar, I'd assume it would have to be 2 bar for turn key to use it on a supercharged set up? And no I dont have the cable/dongle. Now you guys have me thinking,if they made a mistake and put a 1 bar map what would be a symptom ? It feels like its hitting a rev limiter when it gets Into load around 2000rpm
what does your map table go up to?
transam
12-04-2012, 08:41 PM
I don't have the cable/software to be able to see what the tune is like
camcojb
12-05-2012, 12:06 AM
I don't have the cable/software to be able to see what the tune is like
I would not be out loading a supercharged engine with a tune I can't see or know nothing about. ;)
Matt@BOS
12-05-2012, 07:53 AM
Would you also maybe describe the problem as a "stumble?" The was a similar problem on an El Camino at Best of Show with a supercharged 402 from Turnkey, but it has since been resolved after a trip to Westech. Actually, the last three or so cars to go through BOS, including my own, all had a similar issue where the car had low rpm tuning issues. If you can find someone to work with the system it is probably a simple fix.
You could also tear out the computer if there is no one near you that can tune it...
supremeefi
12-05-2012, 08:44 AM
I don't know about 2 or 3 bar MAPs, but the MEFI 4b and 5 are big advances over previous MEFI systems, and even those have more capability than aftermarket systems.
You keep saying that yet no one seems to know if it'll go past a 2 bar map even, it won't do sequential right? It doesn't have a lean alarm, does it have a scaleable map? I could go on and on.
If you would please enlighten us as to how it's better/more capable than the best aftermarket systems today.
I'm with Jody on this one. You have all this time and money in a boosted application. Use something that will protect your investment.
transam
12-05-2012, 08:45 AM
I would not be out loading a supercharged engine with a tune I can't see or know nothing about. ;)
I've done worse,:lol: but it won't even rev past 2000. You can't even give a 1/4 throttle on the car. I pulled the plugs to see that it wasn't too lean.
transam
12-05-2012, 08:55 AM
Would you also maybe describe the problem as a "stumble?" The was a similar problem on an El Camino at Best of Show with a supercharged 402 from Turnkey, but it has since been resolved after a trip to Westech. Actually, the last three or so cars to go through BOS, including my own, all had a similar issue where the car had low rpm tuning issues. If you can find someone to work with the system it is probably a simple fix.
You could also tear out the computer if there is no one near you that can tune it...
I would describe it as a rev limiter. I sent the ECM to turnkey. They claimed it had a permanent 2000 rpm limiter in it,apparently back then they didn't have a time lock break in,they expected you to bring the car back to them and they could look the engine over and then remove the lock. So I was told the lock was removed but the car does the exact same thing. So my suspicion is the lock was never removed. I'm debating if I should try sending it back to them. I will contact westech to see what is their take on it.
transam
02-13-2013, 04:40 PM
So i sent the ecm back to turnkey and they confirmed the rpm lock was removed. So i bought a codemate and ran a scan, im getting a code 41 and a code 81. Is there anything obvious i should check for or start to look at? All cylinders do fire as each primary gets hot as soon as the cars started.
"The code, 81 I am suspecting a cam/crank sensor issue or possibly injector driver problem. The code 41 correlates to the cam/crank issue, which would indicate a bad coil or misfire. A little further investigation on exhaust temps. will tell us more. This is a very strange problem"
GregWeld
02-13-2013, 05:58 PM
Do it right and toss that system and get someone to tune the FAST XFI or similar... You've heard from the best/brightest on here... and for the most part they've suggested you get a more tuner friendly system given that you don't have the USB dongle and cable etc... and you don't have the WB O2 sensors...
Or -- ship the car to Mike -- it's not that expensive compared to the cost of rebuilding your motor...
Just saying -- after reading the thread from the beginning -- you're not getting anywhere going about it the way you are. Summer is coming....
parsonsj
02-13-2013, 06:29 PM
If you would please enlighten us as to how it's better/more capable than the best aftermarket systems today.It's an OEM system with an engineering pedigree that the aftermarket systems can't match. Unfortunately, because it's an OEM system it's mostly locked up, with little aftermarket tuning software support. That's a shame, because with some good software, these systems would be a great value. At this point, without a dongle, cable, and no progress in months, I agree it might be time to throw in the towel and go with a friendlier system.
Edit: if you do decide to throw it away, let me know.
GregWeld
02-13-2013, 07:52 PM
It's an OEM system with an engineering pedigree that the aftermarket systems can't match. Unfortunately, because it's an OEM system it's mostly locked up, with little aftermarket tuning software support. That's a shame, because with some good software, these systems would be a great value. At this point, without a dongle, cable, and no progress in months, I agree it might be time to throw in the towel and go with a friendlier system.
Edit: if you do decide to throw it away, let me know.
Yeah -- It really isn't like me to just butt in to someone's thread and say something like that... but after seeing the dates -- and reading the questions and responses... that's the conclusion I came to. Dude... just spend a few more bucks and get 'er done.
Hey! This may be the first time you and I have AGREED!! A new beginning! <olive branch extended> HAHAHAHAHAHAHA
transam
02-13-2013, 08:00 PM
Its been months because its cold and miserable here and its been sitting untouched. Skiings gotten boring and i have a week to kill before im off to mexico so i figure id mess around with it. I plan to put a fast on it but i do want to sell this mefi set up and would like the buyer to have a working system at least
GregWeld
02-13-2013, 08:04 PM
Miserable NorthWET is an understatement!!
Hey -- I have a buddy that switched from FAST XFI over the FAST EZ EFI... I could see if he's willing to sell his XFI set up?
parsonsj
02-14-2013, 03:37 AM
Hey! This may be the first time you and I have AGREED!! A new beginning! <olive branch extended> Accepted. Hedgehogs and foxes, Greg, hedgehogs and foxes. :)
Back to the OP, the data seems clear. The OP can't see his tune, can't change his tune, and it must be driving him crazy. I once had an old Holley Commander 950 setup that would start and run about every 20 attempts. I got nowhere for weeks. I pulled it out of the car and put in a FAST XFI system and had a running car in a couple of days.
It's time to cut bait on the MEFI, I'd say.
transam
02-14-2013, 07:46 AM
Trust me i cant wait to get the mefi out either, but it does worry me with those codes that there could be an issue that might pop up with the fast, related to the cam/crank sensor or coil packs
transam
02-18-2013, 01:03 PM
Waiting to hear back from turn key, but interesting issue, the car has a real hard start issue that occurs. Turn key said to unplug the cam position sensor, i did that and the car fires up easily each time now, its also driving way smoother, still wont rev over 2k though, i followed the diagnostic procedure to test the cam sensor wiring and everything as far as resistance and voltage and continuity was fine until th last step which was to turn the motor by hand to confirm the voltage goes from 0-7volts. I wasnt getting any voltage from the sensor. Waiting to hear back from turn key on how to proceed. It could be a bad cam sensor, i hope the correct cam sensor trigger timing set is on the motor.:confused59: , kind of glad i went this route or i would be really pissed if i slapped a new fuel injection set up on and had the same issue.
parsonsj
02-18-2013, 02:26 PM
Is there any reason for you not to have a dongle, cable, and tuning software? Have you asked TurnKey about that?
We could probably help if you had those tools. Maybe you posted that in the thread before, if so, sorry to bring it up again.
transam
02-18-2013, 03:03 PM
They were asked about it before but said i had to buy my own, its only a 22k package i cant expect them to throw in a free cable and a means to tune it. Lol. I will probably end up buying the mefi burn because when i go to sell the set up someone will need it anyways. I bought a codemate and it gave me a code 41 and 81, but since its just a mil flasher i dont know what code 81 it is, from my understanding it could be a few different code 81s. When i told turn key about those 2 codes is when they asked me to unplug the cam sensor and see how it ran
parsonsj
02-18-2013, 07:30 PM
My last experience with a MEFI (4b) was also with a TurnKey system. I was having a lot of problems with idle, and couldn't get a consistent IAC response. The problem was that the MEFI wasn't able to recognize when the throttle body was at idle, and so it didn't engage the IAC.
Finally, I reached out to the guy behind MEFIBurn (aka OBD Diagnostics), and managed to convince him to look at the tune. I sent the binary file to him, and he fixed the throttle body settings (there are many) and sent it back to me. His comment was that he was surprised the car ran at all. I had to hack the Ingenius tuning software to allow me to download his tune, but managed to do that, plus get Ingenius to think the tune originated with it so that I could make further changes.
And then the MEFI worked great. All my problems were rooted in the bad throttle body tables -- which are not visible in Ingenius.
Anyway, the point of the story is that MEFIBurn can probably help. And maybe MEFIBurn with a mail order tune will get you going.
transam
02-18-2013, 09:38 PM
Intersting you mentioned that, i was on the mefiburn site today and was looking around on there. Thanks for the advice , i will most likely be going that route in the short term. Thankfully my cars idle is pretty much perfect, but who knows what shape the tune is in.
parsonsj
02-18-2013, 09:44 PM
I think that if you go with the MEFIBurn, you have to load the tune from scratch -- meaning that the original tune (binary file) will be completely lost. Though it seems you're not losing much, lol.
transam
04-14-2013, 03:39 PM
So i decided to ditch the mefi like many of you guys said. I am done with mefi. I started pulling the car apart today and will be removing the mefi set up. I will be going with a fast xfi . I was debating going oem ecm but i dont want to plumb a maf or deal with drive by wire/ or using the dbw to cable conversion. Who would you guys i recomend buying all the f a s t items i need from? Id like to go with someone whos got in depth knowledge and can sell me exactly what i need. Thanks in advance
http://i1035.photobucket.com/albums/a431/ipadguy/CC1FDD93-646D-4CAC-840E-9F84A8B7246A-6106-00000318FC980029_zps2847a483.jpg
GregWeld
04-14-2013, 04:54 PM
Best guy EVER....
Bob Ream -- Imagine Injection -- Glendale, Arizona
602-377-4093
Rybar
04-15-2013, 10:40 AM
Paul what about? http://www.mikenorrismotorsports.com/
transam
04-15-2013, 01:39 PM
Thanks guys,i will be looking at the suggestions,mike norris looks like he has a lot of ls experience.
camcojb
04-15-2013, 01:54 PM
Thanks guys,i will be looking at the suggestions,mike norris looks like he has a lot of ls experience.
Tons of experience, and a great guy also.
GregWeld
04-15-2013, 02:16 PM
^^^^^^^^ X's 2 What he said!!!
Mike Norris
04-17-2013, 05:34 PM
I guess I'm okay :mock: Thanks for the kind words everyone.
transam,
feel free to give me a call and leave a message or e-mail me at
[email protected] and I will see what I can do for you. I use stock GM packages as well as FAST and Holley quite a bit.
Talk to you soon.
Mike Norris
transam
04-17-2013, 09:35 PM
Thanks!,i am almost finished removing all the mefi stuff, going confirm what crank trigger and cam trigger i have and i will be calling with credit card in hand lol
Rybar
09-03-2013, 01:10 PM
we need updates ;)
parsonsj
09-03-2013, 01:21 PM
And what did you do with that MEFI?
transam
09-03-2013, 09:37 PM
Mfi-Ripped it out, sitting on my garage floor. Got really lazy over the summer , just started working on it again. Should have the engine bay done in a few days. And then its on the to rats nest i found behind the dash. I took the new holley harness apart and routed it so it fit my car, took out extra wiring that i wont be using,and cut to lenght extra long runs, redid the injector harness too and thats done. Wll be doing final install thus week.
http://i1035.photobucket.com/albums/a431/ipadguy/024926fac736f6d58b83638f13993adc_zps01e8b167.jpg
http://i1035.photobucket.com/albums/a431/ipadguy/54a085f02a297e5f7deb37d2ea2331c3_zps009997d0.jpg
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