Loping Idle and stumble NOT under boost
Thread Starter
Registered User
Joined: Jan 2003
Posts: 144
From: Colorado
Car Info: 2000 2.5 RS USDM STI block, SOHC heads GT25 Ball bearing turbo, TMIC, TXS BOV, Tial wastgate, etc...
Loping Idle and stumble NOT under boost
My car is pissing me off.... I can barely drive it unless I floor it.. when I am idling it is lopy, and when I am at partial throttle ( normal acceleration) my car jerks, bogs and hesitates. So then I floor it and it is normal and fast as hell. There is a company called endyn (www.theoldone.com) that specializez in honda superchartger upgrades, and one suggestion they have when running a high volume fuel pump, to drill a pressure relief holr in the FPR, thus decreasing idle fuel pressure.. So I did this on my old acura integra (supercharged) and my erratic idle was cured... so then I tried it on my suby, and it seemed to work, but now I get this ****ty drive, and it is embarrasing. Could this be why there is a lopy idle, and horrible acceleration? I did throw a code p0130 which is malfunctioning O2 sensor, bank one sensor one.. so I pooped out my eu and saw there was a bad connection ion that wire.. ( ****ty splice job) so i repaired it and the light went off. but my car is still running like... it is either not getting any fuel under normal driving, or no spark... help help help help help!!!
Guest
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The unfortunate thing is that you know what your problem is and you inflicted it on yourself. The only reason you would do a mod like you performed, would be if the high volume pump was causing an INCREASE in base fuel pressure, which I higher doubt. THe walbro 255 HP pump does NOT raise the base pressure, heck right now I'm running 55 psi static pressure on a customer car, and it runs very well.
Bottom line, your car is leaning out under part throttle/ idle. You need to put in a new regulator either stock or adjustable.
nick
good luck
Bottom line, your car is leaning out under part throttle/ idle. You need to put in a new regulator either stock or adjustable.
nick
good luck
Thread Starter
Registered User
Joined: Jan 2003
Posts: 144
From: Colorado
Car Info: 2000 2.5 RS USDM STI block, SOHC heads GT25 Ball bearing turbo, TMIC, TXS BOV, Tial wastgate, etc...
I figured this was the problem..... but I have had this mod on my car for quite some time, and it only started loping and running ****ty the past month... could this be because I fixed the CEL, and now my car is in "freak out" mode because it doesn't know what is going on.. ig, the presure drop?? and does anyone know where I can get either a stock or adjustable FPR, preferably one that has a fuel gauge built into it. Is there anything else that could be wrong?
Guest
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you might done damaged to the motor, due to the prolonged lean condition you have been running yourmotor under, a slightly damaged piston or ring, will show exactly what your describing.
Put a fuel pressure gauge on it and verify that first, if that isn't yoru problem the first thing I would do is pull the plugs and do a Leak down on the motor, to check for damage.
Have you heard any Detonation over the winter?
Nick'
Put a fuel pressure gauge on it and verify that first, if that isn't yoru problem the first thing I would do is pull the plugs and do a Leak down on the motor, to check for damage.
Have you heard any Detonation over the winter?
Nick'
Thread Starter
Registered User
Joined: Jan 2003
Posts: 144
From: Colorado
Car Info: 2000 2.5 RS USDM STI block, SOHC heads GT25 Ball bearing turbo, TMIC, TXS BOV, Tial wastgate, etc...
No I haven't had any detonation, My plugs are in great condition and I havea timing device that retards timing per pound of boost, and I have it set at 3 degrees PPB, and I am only running 6 psi.. Could my Primary O2 sensor be bad?
Thread Starter
Registered User
Joined: Jan 2003
Posts: 144
From: Colorado
Car Info: 2000 2.5 RS USDM STI block, SOHC heads GT25 Ball bearing turbo, TMIC, TXS BOV, Tial wastgate, etc...
also when i am accelerating it sounds like it is missing.. Could this be bad plug wires ? Just curious
Thread Starter
Registered User
Joined: Jan 2003
Posts: 144
From: Colorado
Car Info: 2000 2.5 RS USDM STI block, SOHC heads GT25 Ball bearing turbo, TMIC, TXS BOV, Tial wastgate, etc...
Yes, it is a MY00 RS with a turbo kit. I posted this in the WRX topic room because I get faster replies and better information.
Guest
Posts: n/a
Ok, well next time put your car specs up. It helps. is your car setting any misfire codes? It could be related to ignition wires. Overhead cam cars have lots of problems with loosing spark through the insulation to the head, under light load conditions, it is normally most prevalent. it they have more the 50-60k on them just replace them with a new dealer set OR Quality aftermarket set. I mean QUALITY....don't be cheap here. If they "look" cheap, then THEY ARE!!!!!!! I fight with this all the time at work.
Nick
Nick
Thread Starter
Registered User
Joined: Jan 2003
Posts: 144
From: Colorado
Car Info: 2000 2.5 RS USDM STI block, SOHC heads GT25 Ball bearing turbo, TMIC, TXS BOV, Tial wastgate, etc...
sorry about the confusion. and thank you for the replies.. I have a 2000 2.5 RS with 27000 miles. I have a walbro RRFPR set at 7:1 ratio. GT25 dual ball bearing turbo, Tial wastegate, 2.5 Inch cat back exhaust. Top mount intercooler, and Turbo XS blowoff valve.. I also have a timing device that will retard boost per psi, set at 3 deg, per psi. I have a voltage clamp set at 4.2 volts.. I have NOT thrown any codes other that p0108.. does this help??
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