RichardPON

Considering there are a fair few techincally minded types on here, and most MR2 owners don't know what is what with an engine, I though I'd post here and try and get a response.

Basically, my car (MR2 turbo) has the followuing symptoms:

Running rich, mental fuel consumption, intermittent missing on boost, poor running from cold, very high idle when cold and warm.

Does this sound like a vacuum leak?

The early 3S-GTE use an AFM, and as standard have a re-circ dv. Mine has a VTA dump valve - this has always been a bone of contention with MR2 afficianados, as obviously any dumped air is not metered. Could this be the cause of my poor running?

Also seems to accelerate so much better on partial throttle, but at WOT it causes all manner of missing etc.....

Any techincal type thoughts would be appreciated, and don't do the whole "this is a Ford forum" thing. At least I'm asking about cars and not what colour sweater I should knit for my pet hamster....

rsnissan

iTrader: (9)

sounds like the AFM itself.........................does it run a hotwire?

Stavros

Air leak somewhere post AFM giving it fucked readings (or fucked AFM, but leaks more likely).

Sounds like every Skyline and SX etc etc with same problem.

Boost pipe split or similar, could even be a lil vac hose thats split.

Or a blowing inlet manifold gasket.

Or leaking DV.

Anonymous

Do you know anyone with an AFM you could swap on to test?

Failing that, some sort of air leak, either the pipework or the DV sounds possible.

When you say its running rich, how do you know that?
What circumstances is it rich under and by how much?

Anonymous

Ps

I think that a natural colour along the lines of beige would be best as he will be too easy for cats to spot if you go for red or similar.

Gregs

could try tiger stripes!

Rab

Mate, thats definately a leak. When I rebuilt the one I ahd it was the same thing. I ended up binning the dump valve and plugging both ends

Anonymous

Scrap it Pon

RichardPON

Cheers guys!

I've found some online multimeter pin out type testing stuff on the net to check voltage outputs etc so will give that a go to check the signal to the ECU, and also the AFM itself.

I know it's running rich by the fact that most of them do, you can smell the unburnt fuel - that is to say I know it's running rich some of the time..... I've not put any AFR equipment on it, although I do have an EGT gauge, but I think the sensor's packed up.

Phil - I could turn it into a 355 replica and it'd still be better than your shonky hair chested 348

Billabong

Slightly off at a tangent, what air filter are you running?

Anonymous

..one that filters air? QUACK

SteveB

iTrader: (3)

Richard I had a similar sympton with a R34 GTR and simply sprayed brake cleaner thru the AFM (took it off the car) to clean the hot wire and it solved the problem....

aduz

and you were asking me if i was on the correct forum u goon

Billabong

Reason I asked, is because AFM's hotwire doesn't like filter oils QUACK

Anonymous

Dont forget that unburnt fuel could be due to an ignition problem, could be something as simple as the plugs need replacing.

rsnissan

iTrader: (9)

indeed that was to be my line of enquiry........

Billabong

Thought it might when you mentioned the 'hotwire'

RichardPON

Done the plugs..........

I know scoobies didn't respond to some of those "oiled" filters....... and fooked up the AFM..

The Filter is an HKS job, but it is widely accepted as being the poniest filter on the market.....

Billabong

But is it an oiled type, Rich?

RichardPON

I don't think so Bill, but with closer inspection, there isn't much filter left!