Cold start problems
Thread Starter
Teching In
Joined: Jun 2004
Posts: 22
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From: Orlando, FL
Cold start problems I have a 99 just put 233/239 112lsa, fast 90/90, prc 2.5 5.3l heads, ps lontubes. The car runs great, drives fine, but in the mornings or after it sits for a while it won't hold an idle. So i have to keep holding the gas to get it to warm up and catch it. What needs to be done to fix this. (my nieghbors aren't to fond of me "revving" my car at 5:30 in the morning if i have to drive it to work. 
Yeah I'm the one tuning the car. HPT 2.20 with stock 99 OS in the PCM. I hate secondary VE's too...lol. It has FAST 36 lb injectors and I was fighting with those for a bit and we were having O2 issues before. Now using C5 rear O2's in it. Those are now taken care of. The car is currently in SD mode, not using the MAF (stock MAF descreened). The IAC Counts are a lil bit high, so was thinking of drilling the TB. It's a NW 90mm. I have heard of people having to drill them. This is my first car with the NW 90. I have done the TPS voltage reset and, if if the TB blade is opened too much, it still seems to want to do the "cruise control" effect. So, I'm thnking of doing the small hole, last case scenario of course.
I'm more of an SD guy as I have had the best luck with SD. My buddy's 402 with a 248/254 runs best in SD. My car is SD as well. I really would like to do MAF on Anthony's car though. I hadn't been using my wideband as it was on my car. I removed it and we are going to install it in his. The VE and LTFT's look good and I really want to dial in the PE table now and get an idea of how far the MAF table is from actual values.
Also, I'm thinking the idle timing may be an issue as well. It's currently 26 degrees at idle. I'm open to suggestions on this one...
Thanks
Steve
I'm more of an SD guy as I have had the best luck with SD. My buddy's 402 with a 248/254 runs best in SD. My car is SD as well. I really would like to do MAF on Anthony's car though. I hadn't been using my wideband as it was on my car. I removed it and we are going to install it in his. The VE and LTFT's look good and I really want to dial in the PE table now and get an idea of how far the MAF table is from actual values.
Also, I'm thinking the idle timing may be an issue as well. It's currently 26 degrees at idle. I'm open to suggestions on this one...
Thanks
Steve
Yes actually I've been playing with the RAF a LOT. It seems the more I add really doesnt help. It just wants to hang up more. Most of the time, the car seems to idle fine. It's when it's cold it acts up and an occasional stall coming to a stop.
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What are your IAC counts on start up? That'll tell you if you have enough air flow on your cold start.
It could also be a mixture condition. I've seen both overly lean and rich conditions cause the same.
Are you using a wideband?
It could also be a mixture condition. I've seen both overly lean and rich conditions cause the same.
Are you using a wideband?
26-27 degrees timing in the idle regions. I have tried the bi-directional controls and this "seems" to be the best. The IAC counts seem to be in the 80's when at idle and MAX out and stay in the 190's when driving around. This is really high, but any more adusting the TB screw seems to make the idle hang up high. Did the resetting of the TPS too. still.
Car needed a shitload of idle air. The IAC was MAXED, And the NW TB was causing an issue. The TB blade could not be opened any farther. using the screw or other means. Fueling was fine. The hole had to be enlarged a cunthair bigger and it was and has been fine ever since. IAC is perfectly in range now.