Singh

My '95 993, 64k miles, has problems on start up.

First, i need to turn the engine a lot before it sparks and starts; then the idle is very rough, chugging. This happens whether the engine is hot or cold. There is a very strong smell of petrol too. Sometimes, this process is accompanied by a lot of white smoke.

Can anyone help? Never had any problems with the car to date.

I had a new ecu chip around a year ago - it has been fine all year. The car has seen 4 track days this year without problems. This problem has come about after around 2 months of very little use.

Thanks

Ajit.

Singh

I forgot to mention, i have always used Shell Optimax or an equivalent high octane super unleaded fuel.

Terry Adams

Just a guess from your symptoms and my experience on a prior 911 at around 60K, one possibility is oxygen sensors.

mpm '95 C4

I had a bad fuel relay (I think it was a fuel relay ), but my mechanic switched it out with a 968T relay and not a problem since...

James_J

Perhaps it's one (or more) of the spark plugs not working. The white smoke may be unburnt fuel - you could take a sniff of it to check (not too pleasant!). When did you last have a full service?

Singh

Thanks for these everyone - I wonder in which order i should address them. I had a full 24k service done in April this year - changed all the plugs - when I remove them to smell, what will the give away signs be? Also, should i do this after trying to start the car?

Something really strange happened when i tried starting the car again after my message - i turned the key and everything (except the warnings lights) was dead. No engine turnover. After a few tries, it went back to turning over and struggling to fire up.

Tito

? the dreaded wiring harness issue - affecting your alternator ??
Good luck either way.
Tito.

Singh

Tito - I hadn't considered that, but I have had to jump start the car when i drive it after its been stationary for around 3 weeks.

The wiring loom shouldn't lead to the problems with the strong petrol smell or wierd chugging at idel though should it?

Tito

Hi,
I dont know to be honest, but I think that it could cause the weird chugging. There may be a knock on effect causing the petrol smell - but I am just trying to make logical conclusions.
Could it be your battery +/- alternator not holding charge?
May be one of the big boys would have a better idea.

Tito

Greg Fishman

[quote]Originally posted by Singh:
<strong>Tito - I hadn't considered that, but I have had to jump start the car when i drive it after its been stationary for around 3 weeks.

The wiring loom shouldn't lead to the problems with the strong petrol smell or wierd chugging at idel though should it?</strong><hr></blockquote>

How long has it been since you changed fuel filters? Maybe it is partially clogged from a bad tank of fuel?

993,951,944

In addition to the other posted trouble shooting
suggestions, check you Idle Stabilizer Valve (ISV). This part requires periodic cleaning
as it gets full of carbon and causing rough idle
or NO idle at all. It's an aluminum cylinder
shaped part with two 3/4" hoses and an electrical connector attached; it's located on top of the intake manifold. This part can also be adjusted
if stalling is frequent.

All the best,

James_J

The full service should cover most of the more obvious causes of these symptoms, but it is worth being sure that the fuel filter(s?) is clear and that there is no water in the fuel.