Evil p38 2.5dse. dropping power in 3rd gear and not passing 70mph + more help

hi all, right ive got a 1996 p38 dse Auto.
so my problems are it will not pass 70mph but if i lay of then refloor it, it will then pull again somtimes it will not clear like the throttle is dead.

if i floor it from 0-60 it feels like someone is shutting the power down.

also gets a random judder at 45mph always 45mph no other rev or speed.

ive tryied a new map sensor and pipe,
all pipes are now good,
drove it with the turbo pipe from the turbo intercooler pipe of to see if it still does it and it does...

took the cat out and yup still does it.

had a service inc gearbox,
new fuel pump.
no injector flashing.
no heavy smoke.

really am stumped.

sometimes get the gearbox fault but once in a blue moon.

also my cruise control dont work but thats not worked since ive owned the car.

erm what else to say it had 90+ but no very often.

can anyone help!?!?! that was it cutting it self out aswell
some videos https://www.youtube.com/watch?v=kdjB8AUx-uA

Mine did a similar thing when i rescued it from its previous owners. I changed the MAF (Mass Air Flow sensor) and my god its like a rocket now (well for a p38)
If you have one check it... clean it with electrical connection cleaner....Being a 1996 I doubt it will have one tho

nope has no maf or egr

High, post your location someone may be local with some diagnostic kit.

good idea, kings lynn norfolk think it maybe the little pipe from the turbo to the actuator? as just drove it with the map pipe of from the fuel filter end and it made no difference

Check fuel flow from Lift pump...

Remove filter bowl, use a measuring jug to catch fuel and turn ignition on.....should get 180ml in 10 seconds.

Also check the spigot on the manifold were the MAP pipe comes from, and check the pipe and the MAP sensor aren't clogged!

Should be a marked difference with MAP disconnected.

The little pipe on the turbo to the actuator on side of turbo is for the waste gate it stopes over boosting, have you checked all the turbo and intercooler pipes for internal delamination that can cause loss of power.

Littlewill means the MAP sensor. have you checked the take off pipe at the manifold for the MAP is not blocked? Ditto at the MAP sensor. Really needs diagnostics, but I would guess the MAP is not operating. I assume the air filter is not blocked?

Datatek said:

Littlewill means the MAP sensor. have you checked the take off pipe at the manifold for the MAP is not blocked? Ditto at the MAP sensor. Really nedds diagnostics, but I would guess the MAP is not operating. I assume the air filter is not blocked?

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As post #6 :

Saint.V8 said:

As post #6 :

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Yep except the air filter and the correction to Littlewills MAF.

Datatek said:

Yep except the air filter and the correction to Littlewills MAF.

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True...

think ive found the problem low atf fluid, topped it up and feels loads better! has its odd moment when it goes under powered but its defo loads better.

k33vno said:

think ive found the problem low atf fluid, topped it up and feels loads better! has its odd moment when it goes under powered but its defo loads better.

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I hope you used the correct topping up procedure?
Good idea to do an oil and filter change, should be done every 24K miles and add a dose of Lucas Transmission Fix.