Well my car finally got lowered off of jack stands for the first time in a year. Setup is PTK street kit w/ a T67, ASP underdrive pullies, 42 lb injectors, 255 in tank, Pro-M 80 mm calibrated for 42 lb injectors but for a cobra comp and I have a GT. We set the timing with the spout out to 7 degrees also. Now while on jack stands earlier today it idled fine and revved nicely. As soon as I tossed the wheels on and tried to pull out, it ran extremely rich and spuddered dieing out. When we pushed it outside I started it back up becuase it instantly filled our garage with smoke. When I started it outside it got a miss in it. Is it possible that the miss is from soooo much fuel in the combustion chamber. It spudders pretty far up RPM wise and never really clears out. Any points on what's happening and where I should go from here. Thanks
disappointing day
- Thread starter 95stangGT
- Start date
Numbles
Active Member
First Id check the firing order and clean the MAF.
Im not too good at diagnosing problems like this but TTT for ya.
Im not too good at diagnosing problems like this but TTT for ya.
The problem could be that only have 7* initial, AND TOTAL if you didn't put the spout back in, if you did put it in then this shouldn't be the problem.
Did you disconnect the battery? If so, I'd either disconnect it again, or try to start it and let it just sit and idle for at least 3-4 minutes. Give the O2's some time to realize you just added a butt load more fuel to it and try to compensate. Do you have any type of tuning devise? If not you may have to get one and have the pulsewdith at idle trimmed way back to avoid an excessively righ condition. If the plugs are fouled, it will miss like you describe. Hope it turns out to be something minor as that should be a KILLER setup when its tuned and running right. Good luck.
Did you disconnect the battery? If so, I'd either disconnect it again, or try to start it and let it just sit and idle for at least 3-4 minutes. Give the O2's some time to realize you just added a butt load more fuel to it and try to compensate. Do you have any type of tuning devise? If not you may have to get one and have the pulsewdith at idle trimmed way back to avoid an excessively righ condition. If the plugs are fouled, it will miss like you describe. Hope it turns out to be something minor as that should be a KILLER setup when its tuned and running right. Good luck.
BTW- what's your plug gap set at? It should be around 40 thousandths to avoid spark blow out. This shouldn't be a problem at idle or it your not into boost.
94TURBO5 O
New Member
Killercanary said:
Big mods always have bugs my friend, but when they get worked out you'll feel some serious hp. That's the thing with taking them apart they never run the same so you gotta just tweak around, the power is in there you just have to extract it out patiently.. I'd do what Paul said for a start and let us know what happens after that.
Killercanary said:
Here's the kicker. When we first set the timing we forgot to put the spout in and it was running nicely. Then when I realized the spout was out I plugged it in and the car died like 5 seconds later.
The battery is constantly being disconnected so thats not it and the car is given enough time for the O2s to adjust.
Plug gap is at .035
94TURBO5 O
New Member
DougNuts
Founding Member
95stangGT said:
Is that the problem? Don't the cobra computers have 24# injectors in the program. That would mean the MAF's transfer function (is that what it's called) would be off by a little.
ex. 19/42 does not equal 24/42
The other idea I had is a vacuum leak of some sort.....
Edit: Am I the only one who feels like they've forgot more mustang info than most people know?
HoofnIt
Founding Member
The cobra computer is different with respect to the injector size. If you still have your GT computer then why not swap it in and see if it makes a difference?
You trying to run 42# injectors straight up? There is no way in hell the car is going to run right with 42's and a stock EEC. My car ran so rich it would shoot 10 foot streams of fuel out the tailpipes. With an injector that large you will have to use a tuning device to change things around a bit. The miss is probably due to fuel trying to foul the plugs out. Been there and done that.
DougNuts said:Is that the problem? Don't the cobra computers have 24# injectors in the program. That would mean the MAF's transfer function (is that what it's called) would be off by a little.
ex. 19/42 does not equal 24/42
The other idea I had is a vacuum leak of some sort.....
Edit: Am I the only one who feels like they've forgot more mustang info than most people know?
I don't think with the way its loading up that would make the big difference
SorsCode
20+ Year Stangneter 
DougNuts
Founding Member
95stangGT said:
Why not? Ever hear what happens when people drop 24# injectors on a GT and don't change the MAF? Runs pretty rich from what I've been told.......
Now, multiply that by the fact that you have huge ass injectors and a small change in pulsewidth means you're roasting marshmellows. I'm not saying I'm right here, but it's something I would look into a bit more.
Like I said above, I've forgotten all of the GT/Cobra computer/MAF differences so I may be talking out my ass. But, if there is a difference in a MAF calibrated for 42#ers and Cobra computer and one calibrated for GT computer, I would wonder if that's the problem. Also, are you getting any check engine lights?
Without a doubt, you need some sort of chip or eec tuner. My s/c only made six pounds of boost, with the 42's just ran like complete junk without my chip. It'll always be way too rich, on the dyno my a/f ratio was way off the scale which stopped at 10:1 at WOT. I didn't even get it tuned on the dyno, I just got a mail order JMS chip and everything was well. A good investment for $325, dyno time is too damn expensive at all the local shops.
UPDATE
Well here's alittle update for today. She lives! lol
Like a few people suggested I played around with the mass air. Started it up and it ran descent. So decided to see if she'll be able to move this time and I had no problem backing her up. Then drove around the large parking lot. You can tell she's alittle rich but other than that ALOT better. The road our garage we rent is on is pretty long and straight. So I waited till it was alittle dusk and pulled it out again. Waited till I saw no headlights in either direction and gave it alittle rip.
I gave it like half throttle, heard the turbo spool and suddenly I was pushed back into my seat. What an awesome feeling. Not to mention that bad boy is loud 
Was running open y-pipe and had no problem hearing it. lol At least now I know tuning won't be so bad once I get the right calibration and stuff. So thanks to all for the suggestions 
Well here's alittle update for today. She lives! lol
Like a few people suggested I played around with the mass air. Started it up and it ran descent. So decided to see if she'll be able to move this time and I had no problem backing her up. Then drove around the large parking lot. You can tell she's alittle rich but other than that ALOT better. The road our garage we rent is on is pretty long and straight. So I waited till it was alittle dusk and pulled it out again. Waited till I saw no headlights in either direction and gave it alittle rip.
I gave it like half throttle, heard the turbo spool and suddenly I was pushed back into my seat. What an awesome feeling. Not to mention that bad boy is loud Was running open y-pipe and had no problem hearing it. lol At least now I know tuning won't be so bad once I get the right calibration and stuff. So thanks to all for the suggestions
Not a good idea to rip on a power adder car without a tune. I learned the hard way by changing head gaskets just a few days after the blower install. Do yourself a favor and head over to a dyno ASAP. JR can also atest to this.
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