Hi All

 

Today (sunday) I went to a local car show in Bristol, Weston Wheels. On the way there, all was fine, the odd bit of smoke on idle (blue), but this I think is due to the PCV valves needing replacing. Anyhow, since having the car, over the past 3 years ive done about 3k miles, and have never had a problem apart from the above mentioned, and some strange idle patterns, maybe again due to the PCV's? While driving down the M5 at about 55mph, a friend of mine was about to pass me so I gave it a bit of Boost (in 5th, foot down), all was fine, untill at about 90-100mph loads and loads of smoke, blue I think came from behind (I assume the exhausts, not underneath). There was masses of it. So I quickly pulled off, turned of the car, had a look under the bonnet (all intact), started up and drove another 25+miles at 90mph with no trouble what so ever?

 

Then this eve on the way home, it started to do it again, but not so bad. A frien behind said it was black smoke, but it smelt of oil. It came from both exhausts. It was a bit intermittent, and not always when you use boost, just randomly smokes?

 

Any ideas? Ive got a week of so need to get it fixed!

 

Thanks in advance.....

 

Karl

Reading some of your previous posts and this one too, it is very likely you have more than one problem, pcv`s just change them, low cost and can only be a good thing.

 

Black smoke when on the power is usually unburnt fuel, however could be due to the lack of use of the car and the cylinders get a bit coked up at the top and your giving it a blow out as such.

 

The other thing to concider is air/boost leaks this can cause incorrect fuelling as the air flow meter is reading a volume of intake air and then you loosing some of it.

 

Do a boost leak check, or get one done using Vijay`s famous boost leak tool ( top bit of kit!) also check all basic engine settings like timing and tps settings throttle balance,vacuum pipe in correct places etc, you need to be sure all the easy items have been covered.

 

A combination of things can cause major looking symptoms, the one failing with the 300zx I think, is despite many incorrect settings or failed sensors the engine will often run on and on, this can lead to an undeserving view that all is ok.

 

Many is the time I spend hour or so sorting a few timing and sensor issues and end up transformed the way the car runs, not through any magic touch, just geting all the base settings back to how they should be.

 

Before you despair of big bills etc. do all the basics settings and checks and your still in with a chance of solving the problem without too much wallet ache.

 

Good luck

 

 

Jeff TT

Thanks jeff

 

I did think it was fuel as it went through £20 of fuel on about 30miles, not realy driving hard as such.

 

Im going to have a tinker, then take it to z world as there just down the road.

 

Many Thanks

 

Karl

:bow: above sounds good to me mate LOL