Ok guys…need some help here. I recently upgraded from the Steg stage IV (if I got my Roman numerals right) to a Whipple running 13psi. Starting slow because my budget has to pace itself before I get all crazy and cough up the loot for the fuel mods required for the extra boost. Anyway..got the car tuned and it put down 519/486. At first the car ran great save for a little hesitation starting out in 1st which was easily correctable with some creative clutch and throttle strategy from a stop. I figured it might be the tune but it wasn’t enough to really upset me. Now, had a couple of kills and was pretty happy with the added power. About a month after I got the car tuned, I noticed a little bit of a hiccup at full throttle and sometimes cruising in 6th. Unfortunately it got progressively worse, to the point where I’m getting really pissed off. I did the usual cleaning the MAF, checking the plugs, vacuum hoses, etc. Everything seems normal. After I did all of this it did improve but not cured. Note: A while back (pre Whipple) while changing the plugs I noticed that one of the wires leading into one of the coil packs, it was hanging by a hair. Of course it was too short to splice. I looked around for a new or used molex plug for the coil with no luck, everyone wanted to sell me the whole wiring harness, new was like $400 and used still too much. Anyway, it was not something I wanted to get myself into, not interested in rewiring the whole damn thing for one plug. So I performed a little surgery, insulated the hell out of my work and everything seemed fine. BTW I don’t suspect this to be the problem but wanted to include in the facts in case I’m wrong. Anyone have this problem before? Any suggestions? It is missing and I can’t figure out why. There are no codes showing up so I’m baffled.:fm: Help!
Help! Engine missfire
- Thread starter FireredSVT
- Start date
check the plug under that specific coil. it will show if its misfiring there.
could be your FRPS (fuel rail pressure sender/sensor)! mine went and threw no codes with the exact same symptoms you have. have you hit the rev limiter at all? best way to find out is pull the vacuum line attached the the FRPS and smell for fuel. also pull your dipstick and check for smell of fuel. if either do, change your FRPS and your oil.
its located at the front of your drivers side fuel rail. mine caused the fuel pressure to be really high, making it run super rich, which caused the nasty misfire.
could be your FRPS (fuel rail pressure sender/sensor)! mine went and threw no codes with the exact same symptoms you have. have you hit the rev limiter at all? best way to find out is pull the vacuum line attached the the FRPS and smell for fuel. also pull your dipstick and check for smell of fuel. if either do, change your FRPS and your oil.
its located at the front of your drivers side fuel rail. mine caused the fuel pressure to be really high, making it run super rich, which caused the nasty misfire.
I just read your advice and went out and pulled the dipstick to check, sure enough it smells like fuel!! I'll replace the FRPS tomorrow, Thanks man!!! I would have spent hundreds of dollars and days of frustration! I owe you a beer! Thanks again!!! :beer:
hopefully that cures it...let us know...
No dice. replaced the FRPS and no luck, same symptoms. The car is running really rich, that's for sure. ran my finger through the rim of the tail pipe, just black. and the car seems to have a surging idle. and there is definately fuel in the oil. Any suggestions? Fuel pressure regulator? Anyone? disconnecting the battery would not reset the tune would it? Not sure what to do here..
I don't believe disconnecting the battery reset the tune? Am I wrong?
I hooked the Preditor and took a look at the trouble codes. It's coming back with "Fuel delivery error," anyone know what that's all about? Injectors? Pressure regulator?
Still having problems. I ran some diagnostics through the Preditor and it came back with a "fuel delivery error" code. Anyone know what this could mean? Injectors? Pressure regulator? The check engine light is still not coming on. The fuel filter is only a couple months old so that should not be it. It seems like it is running pretty rich. I ran my finger on the rim of the exhaust pipe after the car had been idling for a while and it was just black water. Any suggestions?
I hate to ask this, but where are your plugs gapped at?
Might be too big of a gap
Might be too big of a gap
Please describe your problem in detail.
Not the same issue. Your car is completely different.
OP = Fuel filter changed recently? Are you sure your not having any kind of fuel issues? Whether b/c of the tune or the pump?
I would definitely check the Coil/Wire you fixed.
I would get this vehicle back on the dyno with the tuner ASAP and see what he comes up with after you've checked all your bases. I don't see how he could justify charging you to check it out seeing as to how recent the mods were done.
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There is a better way to check if the FRPS is blown, just unplug the harness. Better then blowing $120. When my FRPS went out it would randomly get so rich it could not even stay on.
Have you done the PPRV delete? It is known to cause hesitation.
Unless I am mistaken Terminators do not have a Mechanical pressure regulator. The FRPS tells the computer how much fuel it needs and the computer tells the FPDM what the FRPS needs then it gets done.
Fuel delivery error can indicate a pump failure, pump just not strong enough, or FPDM overheating.
If you are running the stock pump you have definitely exceeded its abilities and it's probably running at 100% duty cycle way more then it can handle. Could be dieing.
Would not explain the fuel in the oil, but should be checked anyways.
It is not mentioned here...are you running on the stock Cobra pump?
Have you done the PPRV delete? It is known to cause hesitation.
Unless I am mistaken Terminators do not have a Mechanical pressure regulator. The FRPS tells the computer how much fuel it needs and the computer tells the FPDM what the FRPS needs then it gets done.
Fuel delivery error can indicate a pump failure, pump just not strong enough, or FPDM overheating.
If you are running the stock pump you have definitely exceeded its abilities and it's probably running at 100% duty cycle way more then it can handle. Could be dieing.
Would not explain the fuel in the oil, but should be checked anyways.
It is not mentioned here...are you running on the stock Cobra pump?
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