3.2 cold Start

[r_towle]

What is the cold start system and how can it be diagnosed?

If I park the car in the barn, it starts.
If I leave it outside for a few days, it turns over fine, just wont start.

Today I squirted a bit of starting fluid in the air cleaner...did not really seem to help, but eventually it started.

It has a brand new fuel pump, dme relay and tuneup.
Its been doing this since before I bought it.

Just turns over with no sound of ever starting....
After about 20 tries (all under 30 seconds to let the starter cool down)
It finally started.

Any ideas?

Rich

[rick-l]

Cold start enrichment is determined by the cylinder head temperature sensor.

You could measure it with an ohmmeter and compare it to the values in the manual.

This isn't exactly like the manual but close.

Temperature Resistance
32 8850
40 6905
50 5117
60 3834
70 2903
80 2220
90 1714
100 1336
110 1050
120 832
130 664
140 534
150 433
160 353
170 290
180 240
190 199
200 166
210 140
220 118
230 100
240 86
250 73
260 63

[tobluforu]

Originally Posted by Eveline198029

cold start system and how can it be diagnosed?I don't know

Leave troll!

[r_towle]

Originally Posted by tobluforu

Leave troll!

What makes you think I am a troll?
I happen to have been a member (and customer) here for a very long time, and I happen to own several porsches..

this is my first 911 and I have questions that I could not find answers to using seach.
If you have nothing positive to add, you are being the troll and just adding to your post count with wise ass remarks.

Lets see if someone can help me....cause that is the great part of the board...friends helping others.

I also happen to have built several porsches using Pelican Parts...and my BMW's

Please keep your negative comments to yourself.

rich

[Rot 911]

Originally Posted by r_towle

What makes you think I am a troll?
rich

Rich, he was referring to the poster in the qoute included in his response. Not you.

I would agree with checking the head temp sensor. If you hadn't mentioned the car starts ok in the barn I would suspect your injectors were leaking down. Is the barn heated?

[Mawa]

I had the same problem in my last travel around Europe, it was really cold, my 911 had an electrical problem with some old fuse. It is really cheap to test. Some times when it is too cold outside it is humid too, so it gives some electrical problem, I am not an expert, but in my case, the problem for now disappeared. Otherwise I do not know, sorry

[jlynch1960]

I was having cold start problems on an '84. Changed out all of the ignition without improvement. Cheech at Rennetech sent the DME out to be reconditioned (some guy in Cal) and it's been starting great ever since even sub zero (as little of that as we've actually had).

[Flat Six]

Rich:

+1 Rick and Kurt re: head temp sensor. But Kurt also points to injector leak down. You mention different starting conditions depending on if parked in/out of barn -- leads us to assume it's temperature related.

But is it possible there's a time difference too? As in parked in barn, left overnight, starts up next day. Parked outside, left several days, hard to start? If so, I'd also check residual fuel pressure and FP check valve, if only to rule them out.

Good luck, hope this helps. Keep us posted?

[markivtruck]

pressure test fuel system for leakdown at test port left front fuel rail 19mm nut see how long it takes to leak down to zero.

[steely]

I had cold start issues traced to an ICV problem. Unheated garage, with hard start and lousy idle only during winter for a couple years. You may want to eliminate that.

[Flat Six]

So Rich -- any update?

[Laneco]

Originally Posted by steely

I had cold start issues traced to an ICV problem. Unheated garage, with hard start and lousy idle only during winter for a couple years. You may want to eliminate that.

Also, just FYI, the ICV can be cleaned, then reinstalled. The price on that repair is RIGHT!

angela