stalling after cold start at 8,000ft
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stalling after cold start at 8,000ft
I noticed over the last couple of days that during cold starts at my current elevation of 8,000ft, the car will stall if I give it any gas right after the engine turns over. if I do not give it any gas it stays running, and runs as normal after a few minutes at idle. the car does not do this at sea level. has anyone else noticed this in their 928 at altitude?
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From: Boulder Creek, CA
I noticed over the last couple of days that during cold starts at my current elevation of 8,000ft, the car will stall if I give it any gas right after the engine turns over. if I do not give it any gas it stays running, and runs as normal after a few minutes at idle. the car does not do this at sea level. has anyone else noticed this in their 928 at altitude?
13,500' last month, runs great.
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From: Denver, CO
Where in South NJ are you that you park at 8,000 feet?
Anyhoo - I live in Denver, 5280, and also have an 85.5. Starting here is fine, but sometimes when I go uphill it'll be cranky. Any vacuum leak will give the computer a much larger problem up high. Check the intake system and correct even a small leak, and see if that cures the troubles.
Anyhoo - I live in Denver, 5280, and also have an 85.5. Starting here is fine, but sometimes when I go uphill it'll be cranky. Any vacuum leak will give the computer a much larger problem up high. Check the intake system and correct even a small leak, and see if that cures the troubles.
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Ha, not in NJ....a few weeks ago I drove 800 miles from San Fran to Seattle. this past weekend I drove 750 miles to Big Sky Montana. the car is running really well, with a couple of minor things: I had to tighten up the headlight buckets, and I swapped in new LED assemblies( not just bulbs). a couple of days ago in Missoula, car would not start...no crank, no click. I was able to get the car started by banging the starter solenoid( after swapping the starter relay). as a proactive measure, I ordered a new starter. last night I drove down to Bozeman to drop the car at a shop that works on Porsches to have the new starter installed. I noticed that while parked here at Big Sky, on cold starts, the engine will stall if I apply throttle immediately after the engine turns over. if I let it idle for a few mins everything is fine. the car is running really well in general. blasting over mountains in MT, OR, WA, etc. speed limit is 80mph over mountain passes and the car is great. its just the minor thing I noticed on cold starts.
I'll be here in Big Sky a couple more weeks, then will either head east through North Dakota or South through Jackson Hole for awhile and then maybe on to CO. "work from home" is not a bad thing if you have the flexibility to decide where "home" is on any given week.
I'll be here in Big Sky a couple more weeks, then will either head east through North Dakota or South through Jackson Hole for awhile and then maybe on to CO. "work from home" is not a bad thing if you have the flexibility to decide where "home" is on any given week.
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From: Boulder Creek, CA
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From: Boulder Creek, CA
Ha, not in NJ....a few weeks ago I drove 800 miles from San Fran to Seattle. this past weekend I drove 750 miles to Big Sky Montana. the car is running really well, with a couple of minor things: I had to tighten up the headlight buckets, and I swapped in new LED assemblies( not just bulbs). a couple of days ago in Missoula, car would not start...no crank, no click. I was able to get the car started by banging the starter solenoid( after swapping the starter relay). as a proactive measure, I ordered a new starter. last night I drove down to Bozeman to drop the car at a shop that works on Porsches to have the new starter installed. I noticed that while parked here at Big Sky, on cold starts, the engine will stall if I apply throttle immediately after the engine turns over. if I let it idle for a few mins everything is fine. the car is running really well in general. blasting over mountains in MT, OR, WA, etc. speed limit is 80mph over mountain passes and the car is great. its just the minor thing I noticed on cold starts.
I'll be here in Big Sky a couple more weeks, then will either head east through North Dakota or South through Jackson Hole for awhile and then maybe on to CO. "work from home" is not a bad thing if you have the flexibility to decide where "home" is on any given week.
I'll be here in Big Sky a couple more weeks, then will either head east through North Dakota or South through Jackson Hole for awhile and then maybe on to CO. "work from home" is not a bad thing if you have the flexibility to decide where "home" is on any given week.
What year car, auto or 5spd, any mods, whats the last thing you touched. These are important.
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car is a 1986.5 S, 5spd. no mods. I have not touched anything other than swapping in LED headlights and swapping the starting relay with the horn relay when I was troubleshooting the non-start issue last week, which turned out to be the starter solenoid. new starter was just installed today and I'll pick the car up tomorrow
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From: Cambridge England
I think the observation that the engine doesn't run properly at your altitude until it has warmed up a bit is significant. In other words until the O2 loop is activated so it can correct what seems like too weak a mixture when the LH is running open loop.
I suggest you go through the WSM procedure to set idle CO with the O2 loop defeated and then also set the idle control as per WSM.
I suggest you go through the WSM procedure to set idle CO with the O2 loop defeated and then also set the idle control as per WSM.