Fraser White

I have an August 95 UK spec unmodified Turbo which has covered 70,000 miles and has a full main dealer history. It is used for two 6 mile journeys each weekday and for trips of varying lengths at weekends.

Over the past 6 months the vehicle has suffered from a power delivery problem that manifests itself when under a hard load – either accelerating from below about 2,000 revs or demanding rapid acceleration from anywhere in the rev band. Under gentle acceleration the problem does not appear. Problem has only been observed with warm engine.

The car will accelerate at first but soon (2-3 seconds later) will lose power – as if the fuel supply was being restricted – before beginning to accelerate again. This "fuel squeeze" can happen 3 or 4 times, resulting in the car "kangerooing" down the road. The rev counter swings wildly in the process.

My dealer (Quenby’s of Baldock) had the vehicle for a week, trying various things but was ultimately unsuccessful in determining the cause. These have included testing the boost valve, HT leads, plugs and coil but all to no avail.

Any assistance gratefully received

Regards

Fraser

Jolly Green Monster

iTrader: (4)

They must have had fun testing the HT Leads.. it doesn't have any..

I would say from the description, mileage and age if it has not had the coil packs changed than that will be perhaps the problem, they are about £50 each and you need all four to be changed.

Otherwise you are on cleaning the boost solenoid with brake cleaner, changing the Lambda sensor, or the MAF sensor.

No way of being more sure than that without more info..

Does the check engine light come on at all?

Would also be worth cleaning / replacing the earthing on the car too.

Fraser White

Thanks for the initial ideas.

No, the engine light does not come on.
What further info would you need to get any further?

Regards

Fraser

Jolly Green Monster

iTrader: (4)

I would reset the ecu. Easiest way is to disconnect the battery over night but the proper way is with the connectors under the dash (by your left knee when sitting in drivers seat, and usually tied back with blue tape) info here
http://www.saxonfields.freeserve.co....iag%20Page.htm

I would say it is coilpacks.. but it is worth cleaning the boost pipes and solenoid out with brake cleaner as the cleaner in a can is only about £5 and takes no time to do.
Reset the ecu.. if still the same then replace the coil packs.
If still a problem then replace the MAF sensor. The MAF sensor on the early car is usually very reliable unlike the newer cars, especially if the car has standard air filter etc.. I am assuming you have owned it for a long while and it was fine before the 6months of problem?

DeanF

iTrader: (1)

Check the plug gap, Recomended .7, If larger than this reduce to it, If stuttering gets better, I.e less, it is a sign of coil packs, High boost apps, (which if car is standard does not apply to you) use a .6 plug gap.

The stuttering may even disapear if the gap has initialy been set to large

Dean

Jolly Green Monster

iTrader: (4)

Good point Dean, one would hope that the dealer checked or replace them, but then if they are telling him it has HT leads then who knows what they checked.

RRH

another vote for coil packs. get a quote before asking your dealer to do them as they could turn out v expensive. JGM suggested approx £50 each, from experience you're looking at closer to £65+ each from Graham Goode, and god knows how much from the dealer. You could replace them yourself if you wanted to save some money.

Jolly Green Monster

iTrader: (4)

Fraser,

Are you in the South East?

Fraser White

Yes, near Hitchin in Herts. I have had the car since July 99. Looking back at my notes from speaking to the dealer after they looked into the problem the items that they switched and tested the effect were coil, plugs, boost solenoid (I don't know whether they cleaned it) and certain electrical connections under the battery?? Sorry, but the last vehicle I owned that I understood was a 1977 Mk 1 Fiesta (hence my HT leads error!!)

cheers

Jolly Green Monster

iTrader: (4)

If the coil packs have never been replaced then I would replace them anyway, hopefully that is the problem.
They need to be tested at the same temperature as they get to on the hot engine and under load rather than the resistance test they do.. ie. it is not possible.
You could reduce the spark plug gaps and if things improve them you know it is spark related.. ie. coilpacks need replacing.

I replaced them on my 96 and it transformed the car, both off and on boost.

Jolly Green Monster

iTrader: (4)

PS: Had you been a bit nearer me I was going to offer to fit the ones off my car to prove the problem was coils etc..

Fraser White

Thanks for the advice and the offer. I think that it's time to find an independent specialist.

Jolly Green Monster

iTrader: (4)

API Engines, Rally Colin (Reading).... eeerrrrmmmm