Runs really rough - Code 212
- Thread starter BrightVa
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Oh snap, I thought I had checked the part #, but must have misread. I did not buy a MAF calibrated for 24 lb injectors.
The housing is from a BBK cold air kit that was on the car when I bought it. The silicone couplings were dry rotted, which was part of the vacuum leaks I fixed by redoing the intake pipe.
The A/C was not on.
It seems like the computer is unable to properly control the IAC. I tested and it has 12 volts, I also tested the wire back to the 60 pin for continuity and it checked good. I tried 2 different IAC's and neither one seemed to do anything.
No, I have never been able to reproduce that code. I set the base timing with the spout out, put it back in, and with the timing light observed the the ECU was indeed advancing the timing as it should.
We've come across two potential issues so far:
24 lb injectors
Mass Air housing that may or may not be worth a doo-doo
Suggestions: Install a set of 19 lb injectors and an OEM MAF housing for troubleshooting.
Vac leaks are still suspect.
That hard bend between the MAF housing and the TB housing may be nothing but is not giving me a warm fuzzy.
24 lb injectors
Mass Air housing that may or may not be worth a doo-doo
Suggestions: Install a set of 19 lb injectors and an OEM MAF housing for troubleshooting.
Vac leaks are still suspect.
That hard bend between the MAF housing and the TB housing may be nothing but is not giving me a warm fuzzy.
First off, I do want to say a big thank you for thinking through these issues for me. Your insights are very helpful and I really appreciate it! Can I get you to further entertain some ideas with me?
- So I've got an engine that likely has a Trick Flow top end kit, with what I believe is more than the stage 1 cam (going by the tall valve covers and the really lopey sounding idle).
- It's running 24 lb injectors, but the MAF is designed for 19 lb injectors
- 70 mm throttle body on a cold air intake
- The computer is bone stock and never been opened or tuned
- I think it runs pretty rich because the exhaust smells of unburnt fuel as soon as it fires up
- It pulls a pretty steady 12 inches of vacuum at idle of 800 rpms (though you have to warm the car up before it will hold idle)
Does it go to reason that the car will need a tune to run this combination of parts (and a new MAF)? I was seriously considering putting an after market ECU in it. I've been reading through many past threads looking for people who run H/C/I and bigger injectors on an untuned stock computer and can't find anyone doing that. I've also been reading and it seems many people would opt for a new ECU rather than working with a 30 year old computer.
I was thinking hard about the Pro M because they have what looks to be a high quality wiring harness solution that doesn't require me to hack up the existing one and piece it together with a new one. I don't mind spending money and time on the car, but I do want my money and time to be well spent.
Feel free to shoot holes in this idea. Its just where I'm at. I have spent quite a few hours looking for vacuum leaks and just can't seem to find any more. It seems like 12 inches of vacuum would be pretty normal for a performance cam? But I'm not sure about that.
Yes.
This is what I would do largely, because it will 'future proof' you for more mods and likely smooth out your current issues.
I've done it. It sucks. I drove across PA on an brand new, untuned combo with 42 lb injectors and a MAF "calibrated" for those injectors. It ran like crap.
There are EEC repair facilities for these. Lots of folks here have done this and had good results.
I get the feeling that here, that mods will continue so, I refer back to my fist comment in this post.
I'm only vaguely familiar with the Pro-M kit. You may run into issues there because you can't tell them what cam you have etc., so, it's going to be difficult for them to customize a tune for you.
Now, a Pro-M kit along with a dyno session and professional tuner that knows which way to look? That's a different story. I think you would actually end up spending [more] by trying to DIY the new EEC, Harness, and Tune.
If you want to DIY and have never tuned before, maybe consider one of the systems that self-tune?
In regards to the intake tubing, think of air like really light water, they do similar things when making turns, turbulence at the MAF can create erratic readings, needs at least 6" or more to straighten out, appears from the pic you're good on that. Now that bend after is kinda tight but at this power level it would have minimal effect but I'd like to see if that could be straightened out but this is not causing the issue, I need to go back to see what has been done, too many things going on right now.
If you do not want to hack the existing harness up then get this:
www.diyautotune.com
If you want sequential injection and more capability then pony up the $$ and get this:
www.diyautotune.com
Either one gets rid of the 30+ year old ECU and gets you into a much better situation than a piggy back chip and having to pay a tuner every time you change something. There is a learning curve and these do self learn but I have heard that a dyno session with a good tuner will definitely help. From there you can take it and make any changes as time goes on.
I bought the MS3Pro for my Coupe but have not installed it to date. I know Mustang5L5 has also bought one and will most likely get his installed way before I get mine done.
Ford Mustang 5.0 SN95 1994-1995 MSPNP Gen2 Plug and Play ECU
Ford Mustang 9495 MegaSquirt Gen2 Plug and Play for the 1994-1995 Ford Mustang 5.0 and 1986-1988 Ford Thunderbird 5.0, installs in under 1 hour.
www.diyautotune.com
If you want sequential injection and more capability then pony up the $$ and get this:
Ford Mustang 5.0 1994-1995 SN95 MS3Pro PNP Plug and Play ECU
The NEW Ford Mustang MS3Pro Plug and Play ECU for the 1994-1995 SN95 Ford Mustang 5.0, installs in under 1 hour.
www.diyautotune.com
Either one gets rid of the 30+ year old ECU and gets you into a much better situation than a piggy back chip and having to pay a tuner every time you change something. There is a learning curve and these do self learn but I have heard that a dyno session with a good tuner will definitely help. From there you can take it and make any changes as time goes on.
I bought the MS3Pro for my Coupe but have not installed it to date. I know Mustang5L5 has also bought one and will most likely get his installed way before I get mine done.
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Too many unknown stuff for me, but..... I think at this point I see an aftermarket ECU in your future.
At the very least send that computer to the ECUXchange to get checked out, inexpensive and fast turnaround.
BTW, have you checked fuel pressure? Looked at the plugs?
At the very least send that computer to the ECUXchange to get checked out, inexpensive and fast turnaround.
BTW, have you checked fuel pressure? Looked at the plugs?
Yes, I would like to have sequential FI. Since the stock ECU runs sequential, I would like this to be an upgrade in every way. I'm not really thinking about it for tuning max power, but rather for the best possible idle and low speed drive-ability.If you want sequential injection and more capability then pony up the $$ and get this:
Ford Mustang 5.0 1994-1995 SN95 MS3Pro PNP Plug and Play ECU
The NEW Ford Mustang MS3Pro Plug and Play ECU for the 1994-1995 SN95 Ford Mustang 5.0, installs in under 1 hour.
I have looked at the MS3 and it is a serious contender for me. I could potentially just buy it and immediately hook it up to the existing harness, which is tempting.
Here are my thoughts on the wiring harness:
The current one is not in great shape. When the prior owner pulled the engine, they cut and spliced a lot of wires. I think everything works and the splices are solid, but nonetheless, if I'm replacing the ECU, I would just assume have a brand new, high quality wiring harness along with it.
I have suspected wiring issues on a few things, but checked continuity back to the 60 pin and it checked good. So I can't say I'm having a problem with the numerous splices, but you probably know what I mean.
Do you have any thoughts on the Pro M system specifically? I was looking at them because of the wiring harness, but also because its a MAF system, and should be able to compensate for the fact that I don't know what cam I'm running. Maybe I'm overestimating its capabilities?
Yes, I agree. It's basically a 90 degree angle from the MAF to the TB. I did the best I could by splitting it across two 45 degree angles. Sort of like hooking up a wood stove and trying to smooth out the draft on the flu pipe.
I'll check and see how long the straight section measures tonight.
Edit: I initially tried running flexible pipe, but couldn't get it to seal up air tight. So I switched to hard pipe.
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Thanks for your reply! If you think of anything else, please feel free. I'm in unfamiliar territory.
I will say that I would like to have a system that I can tune myself.
The only downfall to the ProM is that it does not have the following as Megasquirt so the help in the forums with tuning will be a lot bigger with the Megasquirt based system. Another option is a Holley Terminator X and you can get the harness on it modified to work with your stock dash. I cannot remember who does it but I know I have seen it.
I checked fuel pressure a long time ago. I think it was around 42 psi at idle. I pulled the vacuum hose and did not see any signs of gas in the line.
I have not pulled the plugs lately. I may do that tonight and post a pic. I don't have much experience reading plugs.
Anderson Ford Motorsports has a kit for the Terminator X that makes it work with the stock 60 pin. A company called MF Kustoms makes the adapters. It all looks high quality.
I didn't really like the Terminator because it does not have sequential FI. I suppose I could look at the HP or Dominator. I have not price compared them yet.
All of this talk of a better tuner and ECU are great but you have 12 inches of vacuum at idle. Until you fix that problem, you’re just chasing your tail with everything else. You should have 16-17 inches of vacuum. That fuel regulator is very sensitive to low vacuum at idle, and it’s probably the reason why you have a very rich mixture and sooty plugs likely. Maybe you should try to fix that first and see how it runs before you start changing everything else. Just an idea
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