sp-sp-sputtering

Frank B · 02-20-2003, 05:31 PM

After a good warm up, 15 minutes or so, ( fans are still on from start) I start stuttering and sputtering from a stand still.. power seems a little low, and the amps are jumpin all over the place and eventually settle around 14.. I'm getting reakky concerned.. I can't get the car to the mechanic this week, there is too much going on.. any hints as to what may be going on?....

Frank B

carolinus · 02-20-2003, 05:39 PM

Is a cable to your alternator loose/missing?

Frank B · 02-20-2003, 05:44 PM

missing?// heehee.. I don't think so, or I hope not.. it may be loose I did give the belt a little tweak last week..stopped the squealing B.S. and some of the dimming B.S. how would that affect sputtering and stuttering, my car sounds like Ml Tillis on a very bad day..

carolinus · 02-20-2003, 06:08 PM

Also, the car would only run for so long on just battery power. power availability would be erratic. Voltage in the system could be going anywhere. same thing with a dead voltage regulator.
you mentioned amps going everywhere? or tach?

Have you checked your fuel output?

Trevor · 02-20-2003, 06:11 PM

Grounds?

Roger Hall · 02-20-2003, 06:12 PM

Alternator or voltage regulator regulator may be going.

Frank B · 02-20-2003, 07:50 PM

****ski... would that cause sputtering or stuttered accelleration?.. whenever I'd turn anything on before tightening the belts, alt belt would squeal like porky pig in a scrapple factory..

todwic · todwic's Garage

I'd say try the regulator. You may have overworked your alt. with the loose belt. They aren't meant to charge dead batteries, they are just a 'top off" charger and acc. power fella. Grab a voltmeter and go read what your batt post say when:

before you start it
after you start it
10 min after you start it
after you turn the lights on.

You should have at LEAST 13.5 v at all of those times. take readings from the posts, and then the terminals. If there is any difference, clean your cables.

944S Boyeee · 02-21-2003, 07:49 AM

You may have some spark jumping from the wires.....

Are your plug wires old?

Do you have hood insulation?

Just a thought.....

944S Boyeee

profssr2017 · 02-21-2003, 08:34 AM

To 944S Boyee -

I'm curious - can you explain more on your hood insulation issue?

Thanks

green944 · 02-21-2003, 08:56 AM

I am insterested in this as well.
Thanks

Frank B · 02-21-2003, 12:38 PM

wires are old, I haven't changed them since I've had the car. I suck. I was thinking the timing belt was going, it needs to be done. but I'm not sure a weak belt would cause any sputtering, that feels and sounds to me like an electrical/spark situation. Anyone else concur?..

944S Boyeee · 02-21-2003, 01:32 PM

My issue with the hood insulation is that there was a bulletin or a write-up in the Porsche Manual or something out a while back warning 944 owners (S owners specifically) that if the car does not have hood insulation, the plug wires/dist. wire can arch off the inside of the hood. This can cause a miss, a surge, a hesitation, idle problems, etc, etc.

I have no insulation on my hood and I experience random problems like those I listed above. I can see lil' burn marks on the hood sometimes. I clean them up and they re-appear (but not always in the same spot). I keep the inside of my hood spotless, so it's easy to pick out the lil' black "dusty" mark against the red hood.

I replaced everything (wires, cap, roter, plugs, etc, etc) recently and I still get the tiny burn marks from time to time.

Needless to say, as soon as it warms up, I'm slapping a small piece of something in that specific spot on the hood to stop the arching.

944S Boyeee

Frank B · 02-22-2003, 07:15 AM

hesitating still, but it's intermittent. The problem starts after my car warms up.. I am totally stumped?.. I really need some solid advice here....it's been snowy and raining cats and dogs, could it be a water issue?.. it started on Valentines day, (no precipitation) it was running weak, sluggish, now after a warmup it runs like dog doo from a dead stop. Could this be a Timing issue?.. could this be related to the voltage meter issue that I'm experiencing? It's raining too hard to go out and poke around.

Frank B

carolinus · 07:46 AM

The rain is really gonna mess with your troubleshooting ability. There are so many things you should do at this point that it isn't funny. It could be any number of things, and almost all of them need some sort of testing.

I do have a couple more questions that you might want to look into:

1. Are your spark plugs all of the way in there? The block will provide a better seal when cold (my understanding, at least), and if it was only partially in it could really cause problems when warm. This could eventually lead to the plug coming totally out.

2. Is your intake boot really on there? And all of the hoses running to the bottom? It also sounds like one of your hoses could have just plain split.

3. Idle bypass valve still working? Clamp the hose to it shut when warm, and your trouble should go away if that is the trouble.

4. I once saw a technician pull each of the spark plug wires when the car was running to see if it failed to make any difference on any of them. If it does, that is your trouble. He used a VERY insulated tool for this, though.

That strange voltmeter reading is probably a real indicator here. There are so many things that could be doing it, real testing is the only way, almost.

Post back if you are still fubared after checking these things.

Frank B · 02-22-2003, 07:57 AM

HI Carolinus.
I've never had a spark plug back out on me before. Sounds like a possibility though. I haven't changed them since I picked up the car in October, same wires also. It feels as if it goes out of time after it warms up. Belts are being done this Thursday. I feel that this is the culprit. agree/disagree?