Ok i went out in my car tonight (1993 WRX Impreza) and it was all warmed up so on the last few stints home of the by-pass i thought id open it up a little.

As i was giving it some it was going ok going upto around 6.5k revs no problems, then next time i go down the next bit of road it hessitates at 5k revs like its hitting the limiter at 5k, so i back off a bit then put foot down and it goes back upto 6.5k revs. (could this be down to someone crap taking the limiter to de-restrict it? Or could it be some spark plugas (i remember my cosworth doing that when the plugs where pooped)

There was no smoke coming out the back of the car when letting off/or going on boost as far as i could tell!

I decide to pull over and look at the engine and there was some smoke/steam coming from the top drivers side of the bonnet (not massive amounts and no colour as far as i can tell)

When i opened the bonnet to investiagte it looked like the smoke/steam was coming from around the turbo area but not 100% sure.

It did have a kind of smell to it bit like a burning smell, my friend said it could be oil or some fluid dropping onto the turbo or exhaust, but that wouldn't make it hessiate, my other friend when he came round said it could be turbo seals.

I noticed my dump valve was OPEN when the engine was running but obvoiusly no boost going through it? I guess thats a broken dump valve

So any advice help would be so appreciated it will be going to a garage as soon as i can, what could be the problem and whats prices for

TURBO (stock one)
TURBO (up-rated one if its worth it)

If turbo has gone will i need to change some engine components or just the turbo

I have owned 5 turbo cars and this is the 1st time i have ever had a problem


Thanks Jamie

 

If the turbo is on it's way out then you would get a lot of crap coming out the exhaust (oily smoke).
You could change the dump valve for the standard recirc valve.
Just check the coil packs and plugs as it's fairly easy to do.
Check the rocker cover gaskets as they can leak oil onto the hot bits and cause the smoke.

 

The DV should be open when the engine is idling. So thats OK. Was you low on fuel, or under 1/4 of a tank?

 

Your hesitation problem could be fuel cut dut to overboost or faulty plugs or coils. Do you have a boost guage fitted? Try changing the plugs and inspect the coil packs when you do it. Look for cracks under the rubber boots on the coil packs and replace as necessary.

As myblackwrx says if your turbo seals have given up or on their way then you will get blue smoke out the exhaust. The smoke coming up from around the turbo area can be caused by the rocker cover gaskets leaking on to the exhaust manifold/up-pipe.

 

Good point, especially if you were going around/coming out of a bend at the time.

 

Was the hesitation a rapid series of blips or was it one big blip for a second or 2 like hitting a brick wall?

If its the first i'd say plug or coilpacks, these cars seem to suffer from this.

If its the second then more likely to be fuel cut due to high boost, do you have a boost gauge, if so whats it reading?

I would guess the smoke is a bit of oil on the turbo / downpipe and is a red herring.

Dave

 

ok thanks guys well the blip is a big blip like hitting a brick wall, and i had 1/4 tank in the car on satraight road, i do have a boost gauage its running just under 1bar (i must get a psi guage) its not been chipped and has been de-restricted so it should be running standard boost

Engine Advantages said it is probably a boost cut due to high boost and could be a dodgy actuator, or fuel pump or like said spark plugs and coil packs it will be getting looked at soon as they have a slot.

 

Boost Targets & Fuel-Cut Limits
WRX/STi Saloon ECU's 2C, U8, W6, W9 - As above, 11.47psi (0.79bar)held to redline. Fuel-cut 14.57psi (1.0bar)

The above is what the early wrx run (i had a U8 in my 93wrx)

 

so its cutting the fuel myblackwrx

 

If it's hitting 1 bar i would say so.
I used to get it (mainly when in winter) i cheated and stuck a z4 (from a later wrx) which has a better fuelling map and higher boost and fuel cut so cured it.

 

good thinking mybalckwrx,

why would it go over the boost limit now and again just a fault, looks like time for a remap hehe

 

I had the fuel cut come in at the oddest times but since i wanted a bit more va va voom i got a cheap z4 slapped it in now going for a remap myself.

Have alook at PolarPerformance or JollyGreenMonster.co.uk and i believe Mocom racing have a good deal on at the moment.

https://www.scoobynet.com/trader-ann...inclusive.html

 

Just a question. Was it raining or had you just jet washed it.
The other week I was in the jet wash and there was another Scooby there as well,
when he left he booted it and it did the same thing.(to which I laughed )
But when I left it done the same to me.
Also I was in a restaurant with the family. (little chef) and there was a mass downpour. When we left it happened again.
Just an idea, it could be something getting wet.
Good luck anyway
Paul.

 

nice one myblackwrx thanks

paul&bon, no it hadnt got wet afaik