MG ZT CDTI 160 slower after Injector Replacement and Manifold and EGR cleaning

[Rick-sta]

Wondering if anyone can suggest what to do here.

A couple of weekends ago I replaced my faulty injectors with some second hand injectors from a car which had done 90k miles (my injectors had it according to the t4, worst injectors ever seen although the car drove well with them). At the same time I also flushed out my inlet manifold and the egr value using a pressure washer - they were both quite clogged up. I let both dry out before refitting.

Since then my ZT has lost some power . It's lost some of its kick and definitely feels quite a bit slower. And there is a lack of power at lower revs, mainly below 2k revs. So for example, 40 to 60 performance in fourth gear and 50 to 70 performance in 5th gear has gone down hill.

The cars also been more smokey than it used to, but I don't know if I'm only noticing that now after having the back box changed on the weekend, the last back box was nackered and had holes all over the place.

The injectors I purchased from a member on the forum and had been tested, but they're not refurbished and haven't checked them with a t4 yet. But my ZT idles a lot better with them so I think they are better than my old injectors.

Also, I've made sure that the inlet manifold and EGR is secured tightly with no gaps and that all the seals are in place. I've removed and refitted the manifold a couple of times now just in case I fitted it incorrectly and it's made no difference.

Also, my maf is disconnected and has been since before I changed the injectors so its not being caused by that.

Anyone have any suggestions on what to check? I will be doing a full service this weekend to see if it makes a difference, so PCV filter, fuel filter etc will be changed. The car also has a new in tank fuel pump fitted a few weeks ago.

I also currently have Forte injector cleaner in the system at the moment.

Can anyone help?

Cheers,
Rick

[klarzy]

Could you have disturbed the o-ring connection to the turbo intercooler, this would let boost pressure escape and drop power, easily done when disconnecting the EGR system, also are you sure all seals are in place on the air intake / engine interface?

[Jakg]

When I cleaned my inlet manifold it was extra smokey for a couple of days as some soot was still in there, but had been "loosened" so came off with time.

[Rick-sta]

Originally Posted by klarzy

Could you have disturbed the o-ring connection to the turbo intercooler, this would let boost pressure escape and drop power, easily done when disconnecting the EGR system, also are you sure all seals are in place on the air intake / engine interface?

Yeah I've been thinking that this may be the cause, as I did move the intercooler hose quite a bit while it was detached from the manifold and egr value. I've already ordered some O rings so hoping that this will solve the issue this weekend.

I've checked all the seals a couple of times now and theyre all in place and nice and tight None of the seals are damaged either.

When I cleaned my inlet manifold it was extra smokey for a couple of days as some soot was still in there, but had been "loosened" so came off with time.

Mine was almost constant black smoke for a while so I took it down a duel carriage way and most of it cleared. But if I just rev the car a cloud of black smoke can still spew out. Before, there was smoke being a diesel but it was never really black like it is at the moment

[rasa]

could it just be ya egr knackered

[James.uk]

Who was the T4 operator? If it wasn't one of "our" guru's, then they may have returned the ECU to standard 116 when it was a 131..

What were the readings on the replacement injectors? Better? Worse?

Leaking "O" rings don't always cause a big loss in power, in my case, I didn't notice any difference after they were replaced, as the pipe was a very tight fit anyway..
...

[Rick-sta]

Originally Posted by rasa

could it just be ya egr knackered

I've ordered an EGR bypass today aswell to rule that one out. Will be fitting this weekend.

Who was the T4 operator? If it wasn't one of "our" guru's, then they may have returned the ECU to standard 116 when it was a 131..

What were the readings on the replacement injectors? Better? Worse?

Leaking "O" rings don't always cause a big loss in power, in my case, I didn't notice any difference after they were replaced, as the pipe was a very tight fit anyway..
...

It was PhilT4 who checked my old injectors but haven't had the new injectors checked yet. But the car does feel smoother with the new injectors.

I had the 160 done while I had the old injectors in and the car shifted really well. Putting your foot down in second gear knocked your head back a bit. But now its sluggish.

My intercooler pipes pretty nackered, totally covered in grease towards the bottom and a little grease over the rest.

[klarzy]

Originally Posted by Rick-sta

I've ordered an EGR bypass today aswell to rule that one out. Will be fitting this weekend.



It was PhilT4 who checked my old injectors but haven't had the new injectors checked yet. But the car does feel smoother with the new injectors.

I had the 160 done while I had the old injectors in and the car shifted really well. Putting your foot down in second gear knocked your head back a bit. But now its sluggish.

My intercooler pipes pretty nackered, totally covered in grease towards the bottom and a little grease over the rest.

GET THE O-RING KIT...!

[Rick-sta]

Originally Posted by klarzy

GET THE O-RING KIT...!

Already ordered fitting this weekend

[Jakg]

Originally Posted by James.uk

Leaking "O" rings don't always cause a big loss in power, in my case, I didn't notice any difference after they were replaced, as the pipe was a very tight fit anyway..
...

A loose boost hose will cause a *PLUME* of black smoke and no power.

When fitting a new intercooler I didn't put it back together properly and blew a hose off. Trust me, you'd noticed the difference!