rnridout

I didn't know if you experts kept following threads after a while or not, so I am putting this on a new thread. Thanks for your replies. unfortunately, changing the DME Relay did not fix my problem. By the way, the one in the car looked very new.

Anyway, i think I have found one symptom that occures consistently. If the car is started cold and allowed to sit and idle to warm up, after a couple of minutes, before the car gets warm, it will start sputtering (choking down) like it is going to die. I can jump in it, pump the gas a bit, and after a couple of minutes of that, if I can get it revving, and take off, it will go ahead and take off with some reservation. Then, after a couple of minutes, it clears up and appears to run fine.

I thought this running problem after sitting and idling a bit might help you experts diagnose the problem. Are there any repurcussions from having a little bit too much oil in the car?

Any further suggetions you guys can give would be appreciated.

InTheAir

This is going to sound funny, but why let it sit there and idle to warm up? There are threads here that suggest that, when cold, start the car, give it 30-60 seconds to get things pumping, and then drive it. Keep the RPMs under 3000 until it is fully warmed up, then have fun.

Do you have the same problems if you do the above??

rnridout

I have always subscribed to that theory of drive them under 4000 rpms to warm them up. In both cases this occurred, I went back in the house for some reason, and this occurred before I got back to the car to leave. It should not do that though, right? I don't know if you read the other thread, but most times, it happens when I take off immediately, in the lower gears, but usually on the second drive of the day, after the car sat for an hour or so after the first short drive????????

rnridout

I just mentioned the idling thing because this appears to be one way I can induce the problem. I think it helps to solve it if the behavior is predictable.

SwayBar

A link to that/those thread(s) would be helpful.

InTheAir

https://rennlist.com/forums/993-forum/259255-need-help-w-95-993-running-problem.html

TomF

Without looking at the other thread: check the ISV. I am beginning to think that they need to be cleaned every 15K or so.

Robin 993DX

Another possibility is that there is something wrong with your mass air flow meter.

So once the car is warmed up does the idle behave badly?

Clogged fuel filter also?

Red rooster

The idle problem sounds like maybe a warm up enrichment issue or slow lambda probe.
Warm up enrichment is the DME acting like a choke - it increases fuelling when it is told that the motor is cold . So if the head temperature sensor is bad then a garbage in/garbage out situation develops.Fuelling can be anywhere .
If the Lamda probe is faulty/slow operating it is telling the DME nonsense about the fuelling.This problem shows itself more at lower motor speeds.

These are just two probabilities ! with others lurking .
A bad MAF usually stays bad so the motor never runs right.
To sort this out, a session with a PST2 / Hammer should help point at what is going wrong !

I would not just fire parts at your car until you get better DME sensor input information .
This kind of stuff can be a PIA.

Good luck,

Geoff

4sound

I suggested you check the head temp sensor before. When they are bad, a common symptom is the engine will cut out when at a warmed up temp.
What is a " Little bit too much oil " ? Look at the air filter element and make sure there is not any oil on it. Last guy I heard say his 993 had a little bit too much oil, had the oil changed at some quick oil change place, and as you can guess they fill it up cold, then shut the engine off after running it for under 60 seconds and filled it up to the full line on the dip stick. I cant remember ever seeing anything smoke and leak oil like that car did.
I would think this is not your problem, but just for the heck of it, take a quick look.

vjd3

I had a problem on an 88 Carrera that mystified everyone, it would start fine, idle great, when it got warm, occasionally it would "bog down" and not accept throttle at all, it would buck, and almost stall, impossible to drive, but idle fine, but if I managed to goose it up over 3000 rpms for a 20 seconds or so then it would clear itself and behave normally. It turned out to be the throttle switch, which shuts off fuel when you take your foot off the gas to trim emissions, it was reading throttle closed when it wasn't. I don't know if there's something similiar on the 993, but it was difficult to diagnose because, of course, it wouldn't do it in front of the mechanic.

rnridout

Wow, thanks for all the suggestions guys. Sounds like I am going to have to break down and take it to the mechanic to put on the tester. Only think scary about that is what I mentioned previously, that he said I probably broke a belt in the distibutor, and I haven't heard anyone else say that. I live in a place that makes taking it in fairly difficult.

Can anyone answer the suggestion by vjd3 about a similar throttle switch on the 993s, because his symtoms sound identical?

axl911

Are there any check engine warning light? Is your check engine light bulb burned out?

Usually, if there is a problem with sensors or throttle switches, it will throw a code.

I played /w my throttle cable adjustment. Overtighted the cable and my 964 C2 threw a code b/c the idle microswitch is not of position.

rnridout

Thanks. The light works and it is not illuminating.

By the way, drove the car to work this morning, took it easy on it until warm, pushed it a little more, and it ran like a champ the whole way.

JasonAndreas

rnridout,
Do you own a multimeter? A Bosch hammer or PST2 will definitely make the diagnosis a lot easier but with a multimeter (voltmeter & ohmmeter) you can check all the sensors fairly easily and you won't have to drive all the way to your mechanic (where are you located?)