MG & Rover - XPower Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter #1
HI

i went and had a vvc conversion done one my zs 120 mkII it took nearly 5 weeks before the dealer was finished he had several problems with the camshaft positing sensor.
but now my car won't accelerate to the normal limit of 7200 rpm but rather is limits to 6500 rpm
i have never driven a vvc engined car so i can't compare but i didn't feel a noticeable difference in acceleration.
could it be that the problems with camshaft sensor still aren't solved. and that the dealer just stopped trying hoping that i didn't know the difference?
any input would be greatly appreciated
 

·
Registered
Joined
·
3,492 Posts
Cam shaft sensor should not prevent the car going to 7200 rpm,
did the dealer change the ECU, this is where the limiter is controlled.
 

·
Registered
Joined
·
3 Posts
Discussion Starter #4 (Edited)
Are you talking about a whole replacement engine and ECU being fitted?
no only the cilinderhead,intake manifold,the ecu and cable loom etc...
so not the whole engine.

Cam shaft sensor should not prevent the car going to 7200 rpm,
did the dealer change the ECU, this is where the limiter is controlled.
yes the dealer replaced the ECU al parts came from a zr 160 donor car.
 

·
Registered
Joined
·
282 Posts
That today shouts out incorrect ECU, what is the part number on the ecu, does it have either NNN000100 or NNN000160 on the sticker as they are the true 160 VVC spec ecu's. As it is only revving to 6500rpm that will be due to the ecu being for a stanard MPi engine with a 6700rpm rev limit.

The other cause for low cut rev limit is the VVC solenoids plugged incorrectly and need to be swapped around with each other, this will usually cut the rev limit to 5500rpm.

How come the conversion took 5 weeks, was this because parts had to be gatherd for the conversion or they had problems? as the conversion can be done in a day if you have all the correct parts ready and know what you are doing.
 

·
Registered
Joined
·
3 Posts
Discussion Starter #6
the number on the ecu sticker reads NNN000100.
and the reason it took so long is because he had problems with the camshaft positing sensor: its signal didn't get trough to the ecu so the vvc mechanism froze up. and now it seems the problem still isn't solved.
 

·
Registered
Joined
·
11 Posts
the number on the ecu sticker reads NNN000100.
and the reason it took so long is because he had problems with the camshaft positing sensor: its signal didn't get trough to the ecu so the vvc mechanism froze up. and now it seems the problem still isn't solved.
VVC position sensing is crucial - there is a map which lowers the rev limit when stiction or sensing problems occur and this sounds like your problem.
Note non VVC engines are mostly limited to 7000.

Diagnosis of actual vs target cam position will show the error which should run under a 2 degree tolerance to avoid triggering the issue..
 
1 - 7 of 7 Posts
Top