05 Citroen C4 lacking power and struggling to rev

[Off_Da_Wall]

C4 coupe VTR+ 1.6 16v Tu5JP4. Recently had a timing belt pulley shear it's bolt clean in the engine block causing internal damage. So took a change on a used engine from a 05 206 sport. So I've swap all my parts over to the "new" engine and change the timing belt while it was out of the car. Car runs but it's struggling to rev. It has no power under 3k rpm. I checked the timing twice but can't see anything wrong. I've practically changed everything on the engine from my parts car which was known good. Anybody know what I can look for to solve this. I've convinced myself that there's an issue with a inlet valve or 2 as it's revving like it under load and popping into the intake.

[paul_c123]

Does it have VVT?

Another thing it might be is a blocked exhaust/cat, depending on how badly the previous engine failed.

I am guessing there is no EML on, otherwise you'd have looked at this?

[Off_Da_Wall]

said:

No doesn't have vvt

[Off_Da_Wall]

paul_c123 said:

Does it have VVT?

Another thing it might be is a blocked exhaust/cat, depending on how badly the previous engine failed.

I am guessing there is no EML on, otherwise you'd have looked at this?

Yeah detached the exhaust after cat and no difference. Swapped the cat with one from my parts car and no difference. No EML

[richhead]

From what you are saying it does sound like a timing issue of some sort

[GVK]

Not too familar with C4 s but how are the spark plugs connected? Common coil pack or seperate leads? Firing order could be wrong.

[LordLoveLength]

Are you sure your timing marks are correct? As it’s an unknown history on the engine, I’d pull no1 plug and check the tdc mark is actually tdc. Then check the cams are where they should be - could be a slipped or misaligned pulley.

[Off_Da_Wall]

LordLoveLength said:

Are you sure your timing marks are correct? As it s an unknown history on the engine, I d pull no1 plug and check the tdc mark is actually tdc. Then check the cams are where they should be - could be a slipped or misaligned pulley.

The cams and crank are keyed so they shouldn't really move.

[Off_Da_Wall]

GVK said:

Not too familar with C4 s but how are the spark plugs connected? Common coil pack or seperate leads? Firing order could be wrong.

They use a coil pack so firing order isn't a issue

[itcaptainslow]

LordLoveLength said:

Are you sure your timing marks are correct? As it s an unknown history on the engine, I d pull no1 plug and check the tdc mark is actually tdc. Then check the cams are where they should be - could be a slipped or misaligned pulley.

This, and carry out a compression test, which will reveal a lot.