LT1 stalling.
03-25-2011, 10:47 PM
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LT1 stalling. 1994 Procharged LT1.
When I pulled it in the garage for the winter it ran fine. I did a bunch of work to it, mostly cosmetic and minor stuff, over the winter. I pull it out for the time on Tuesday and after it gets warmed up it stalls after about 45-60 seconds of idling. It will fire right back up idle perfectly for 45-60 seconds and stall again. It will not stall when its cold and idling high or when driving it. The throttle response does seem a little jerky when first depressing the pedal or when barely resting your foot on the pedal going down the road and letting off. That might just be my imagination or me not used to driving the car in the last 5 months, not sure.
I have checked for vacuum leaks, loose grounds, etc. The only thing I can think of that I did that would have any effect on idling whatsoever is that I eliminated the PCV system. It was a 2 hose system with an elbow coming from a valve cover and the PCV valve in the IM and both hoses running into the intake elbow in front of the blower. I then put an "abbreviated" PCV system back on it. I ran a hose going from the PCV valve to a vacuum nipple on the TB and it made no difference.
Any advice on fixing this thing?
When I pulled it in the garage for the winter it ran fine. I did a bunch of work to it, mostly cosmetic and minor stuff, over the winter. I pull it out for the time on Tuesday and after it gets warmed up it stalls after about 45-60 seconds of idling. It will fire right back up idle perfectly for 45-60 seconds and stall again. It will not stall when its cold and idling high or when driving it. The throttle response does seem a little jerky when first depressing the pedal or when barely resting your foot on the pedal going down the road and letting off. That might just be my imagination or me not used to driving the car in the last 5 months, not sure.
I have checked for vacuum leaks, loose grounds, etc. The only thing I can think of that I did that would have any effect on idling whatsoever is that I eliminated the PCV system. It was a 2 hose system with an elbow coming from a valve cover and the PCV valve in the IM and both hoses running into the intake elbow in front of the blower. I then put an "abbreviated" PCV system back on it. I ran a hose going from the PCV valve to a vacuum nipple on the TB and it made no difference.
Any advice on fixing this thing?
04-03-2011, 02:01 PM
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I replaced the IAC and the left O2 sensor that was acting goofy. My MAF readings were between 11-14 gps at idle. I replaced the MAF sensor and now my readings are 7.5-10.5 gps. It still has a slight stalling issue, not nearly as bad, and throttle response driving down the road seems normal.
When I remove the vacuum line for my bypass/blow off valve and cap the nipple, my MAF readings are a steady 5.6-5.8 gps and it idles perfectly. What gives?? What should my MAF sensor readings should be being that its Procharged? And why is disconnecting the bypass valve correcting my idle and changing the readings whenever it recirculates behind the MAF?
Any advice?
When I remove the vacuum line for my bypass/blow off valve and cap the nipple, my MAF readings are a steady 5.6-5.8 gps and it idles perfectly. What gives?? What should my MAF sensor readings should be being that its Procharged? And why is disconnecting the bypass valve correcting my idle and changing the readings whenever it recirculates behind the MAF?
Any advice?
