another holding back Pulsar

[Anonymous]

Please please help me with my R before I torch the bloody thing :x

The car is perfect when I start it but about ten minutes into my journey
it starts holding back badly. The car idles, revs, and boosts fine but
driving it is a real pain. But the weird thing is that if I turn the car off for
only say ten seconds its cured itself for ten minutes then the problem
repeats again. Lots of people have told me before that its the car going
into 'Safe Mode' but surely it wouldn't boost like normal if it was going into
this 'Safe Mode'. I've gone though all the archive problem searches such
as heatsoak and hesitation but nothing really there to help.

The ECU check is all clear (5-5) and the car is standard.


Things that have been changed to cure problem but haven't helped:

full mongoose with de-cat
removed exhaust temp sensor
uprated Walbro fuel pump
fuel filter
leads & plugs
distributor
distributor cap
rotor arm

Please help

 

[Fast Guy]

Do you notice a boost difference when it starts holding back? You might have an air leak some where or a MAF problem.

 

[zia]

hi check the maf connection and that there is no crap in it.check det connection.what probably happening is that the car might be det and the timing is been reduced by the ecu. check the timing on idle and revs to make sure the ecu is advancing it. what petrol do you use? and and what boost level is it on, is it chipped or anything?

zia

 

[Anonymous]

Thanks alot for the replys
The car is standard apart from a full de-cat Mongoose.
I use Super Unleaded as theres no Shell garage around here to get Optimax. :roll:
I only have the standard boost gauge to go by but when the car is fine is reads 500mmHg and is unchanged when it decides to mess about.

If there was an air leak how would turning the car off then back on affect it? :?

If it was det wouldn't it change boost as well as timing? :?

 

[Olly]

Ignition module fault???? miss firing under load at a consistant rpm position?

 

[Anonymous]

No misfire at all just a big hold back.
I can put my foot to the floor and it picks up slowly but not like it should,
I turn it off then back on and its fine.
It boosts as normal the whole time. :?

 

[bean]

Mine is doing exactly the same thing, I've done the ECU diagnostics and it's come up 34, so det sensor.

Most likely a fault in the circuit or a plug rather than the actual sensor, so I'm told. :roll:

Not had a chance to investigate any further yet.

 

[zia]

det sensor only retards timing.if you had aboost leak you,d hear it and the idle would be erratic.

zia

 

[Davey]

iirc, the det sensor retards timing, richens the mixture, and cuts boost.

I may be wrong(prob am) but shouldnt the car normally boost to 7mmhg :?: and drop the boost down to 5mmhg when in safe mode?
Has your car still got the standard boost solenoid, and is it still connected properly, cos if it aint, the ecu cant control boost no matter what.
It may just be detting cos of incorrect timing?
Cheers, Dave

 

[Fast Guy]

iirc, the det sensor retards timing, richens the mixture, and cuts boost.

I may be wrong(prob am) but shouldnt the car normally boost to 7mmhg :?: and drop the boost down to 5mmhg when in safe mode?

Cheers, Dave

700mmhg is just under 1bar. Mine was running about 550-600 as standard, it's slightly over that with the Dawes fitted.


Ignition timing out??

(Air leak, probably wouldn't reset if you turn the ignition off)

 

[GINGA]

sounds like its going into safe mode as thats exactly the symtoms when it does it you may also find it pulls nicely till say 2500rpm them you feel it drop off and hold back badly? its also normally fine when the engines cold until it warms up?
Try running a full bottle of injector cleaner through the system when theres only around 1/4-3rd of a tank of fuel left also change the fuel filter as it may be blocked causing a weak mixture and det and check to make sure theres no rattling/tapping noises coming from the engine when revving under light load