Odd 3rd gen problem.
05-17-03, 11:39 PM
#1
Full Member
Thread Starter
Odd 3rd gen problem.
I have an FD that is experiencing an odd problem. It's stock except for the downpipe and exhaust.
The car starts right away whether it is hot or cold. When the car is cold, the engine revs fine - it can go all the way to redline. However, as the car begins to warm up, it has trouble revving. It's as if it hits fuel cut - lots of stumbling. Once the car gets hot, it won't go past 3500 or so. I checked the coolant temp sensor with a multimeter, and it appears to be within range.
A friend of mine had similar problems on his FC, but I don't know if it was the same problem. Does anyone have an idea, or perhaps a FAQ to point me in the right direction? I apologize in advance if this is a topic that has been beaten to death. I tried searching the forum, but for some reason it lcoks up when I do that.
The car starts right away whether it is hot or cold. When the car is cold, the engine revs fine - it can go all the way to redline. However, as the car begins to warm up, it has trouble revving. It's as if it hits fuel cut - lots of stumbling. Once the car gets hot, it won't go past 3500 or so. I checked the coolant temp sensor with a multimeter, and it appears to be within range.
A friend of mine had similar problems on his FC, but I don't know if it was the same problem. Does anyone have an idea, or perhaps a FAQ to point me in the right direction? I apologize in advance if this is a topic that has been beaten to death. I tried searching the forum, but for some reason it lcoks up when I do that.
05-18-03, 12:19 AM
#2
Almost sounds like limp mode, can you make any possitive boost pressure at all?. Disconnect the battery, step on the brake pedal for 20 seconds, reconnect and see if it's still does it.
When you say "exhaust" do you mean catback or do you mean a midpipe too?
If you have a DP, MP, and CB, with no fuel computer your are asking for trouble, mostly with boost creep.
Unless your wastegate is ported anyway.
Do you fans come on at all? I had a similar situation when my fan controller went out on me (put me in limp mode)
Try the battery disconnect first and see if that works, let me know.
Frank
When you say "exhaust" do you mean catback or do you mean a midpipe too?
If you have a DP, MP, and CB, with no fuel computer your are asking for trouble, mostly with boost creep.
Unless your wastegate is ported anyway.
Do you fans come on at all? I had a similar situation when my fan controller went out on me (put me in limp mode)
Try the battery disconnect first and see if that works, let me know.
Frank
05-18-03, 12:32 AM
#3
Full Member
Thread Starter
Sorry, not totally stock. The car has an old GeForce modified ECM so the car shouldn't be blowing up. The car has a down-pipe and mid-pipe combo.
05-18-03, 01:40 AM
#4
Lucky
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Well here are my thoughts. It shouldnt go to redline perfectly cold, these engines hate running hard, cold that that is. Secondly I would pull that supposed G-Force ecu of yours. If you are running a dp, midpipe and catback with a stock ECU you will hit fuel cut. How do you know you have a G-Force ecu, did you buy it or did the previous owner say it was on there??
05-18-03, 01:54 AM
#6
First things first, I would recommend avoiding revving the car to redline until it is warmed up. I am sure that mine would rev to redline just fine when cold, but I don't want to test out that theory. 
Driving hard with a cold engine is bad for the engine. The double-throttle system (secondary runners are closed by throttle plates until the engine warms up) will usually cause the car to stumble if you try to rev to redline under boost anyway.
When it is warm and you try to rev it out, are you doing so under boost or just a light cruise up to redline? Try it both ways and see if there is any difference. If it is only under boost, it might be a fuel cut. Fuel cut is usually a hard cut though, rather than just a stumble. Maybe you would get a few hard cuts as the boost rises and falls as you approach redline with the pedal down, but a stumble would be more subtle.
-Max
Driving hard with a cold engine is bad for the engine. The double-throttle system (secondary runners are closed by throttle plates until the engine warms up) will usually cause the car to stumble if you try to rev to redline under boost anyway.When it is warm and you try to rev it out, are you doing so under boost or just a light cruise up to redline? Try it both ways and see if there is any difference. If it is only under boost, it might be a fuel cut. Fuel cut is usually a hard cut though, rather than just a stumble. Maybe you would get a few hard cuts as the boost rises and falls as you approach redline with the pedal down, but a stumble would be more subtle.
-Max