[ald17]

Hi all newbie here first post hoping to get some advice,
I have a r53 mcs running 220bhp
Well I did before my head gasket went ? sadly since replacement car is very underpowered estimate around 10% + down.
Only symptoms are engine pinging and every now and again the revs bog at idle then catch. I am thinking the mechanic has skipped a timing tooth. But looking for advice.

 

[ald17]

It was just the head gasket that was changed so knock sensor wouldn't have been removed, and I'm sure it would throw a code. Don't see how I can loose about 20 hp and lbs unless the mechanic has done something wrong the only thing I can think of is timing. Thanks for reply

 

[ald17]

I am aware how easy it is to set the timing, which is why I am thinking it might have somehow skipped a tooth by accident.
I have found a fair amount of what seems to be dirt in the bottom of the fuel pump casing today and am wondering if maybe the fuel injectors have got clogged? I did have access to a spare pump and O2 sensor so I have tried with these but no change. I also have a set of standard mcs fuel injectors that I can check incase but if its not that then I am going to have to leave it back with the mechanic.

 

[ald17]

Yes I have been told that as long as the oil pump isn't disconnected it can't skip. Maybe they haven't fitted the gasket correctly incorrect lbs setting maybe I have on occasion heard a gasp of air escaping when I switch the engine off. But if gasket wasn't sealed right wouldn't it be either pressuring the coolant or mixing with oil?

 

[ald17]

I did have a faulty bypass valve but replacement upgrade from 132* min* and wouldn't explain pre det. Will leave back to mechanic and find out I guess.

 

[ald17]

Yes 14% , cat back, stealth cai, 380cc injections, ngk iridium 7, big intercooler. I have reset adaptions made no difference.
Leaving it back with him on Friday

 

[ald17]

Thanks all but no codes both o2 sensors and catalyst issues throw fault codes but I have changed o2 to be sure, No coolant in oil and no oil in coolant also not burning any oil.

 

[ald17]

Always run on super. This lack of performance,idle drop and pre det has only occurred since head gasket went. I am trying to find out what could have caused these symptoms from a head gasket change

 

[ald17]

What was the old head gasket OE or aftermarket?

Did you replace like for like i.e OE for OE/upgraded aftermarket with upgraded aftermarket?

Kit was from 132* full gasket kit so both manifolds and thermostat +head gasket+arp bolts. Doubt the issue is with gasket as it is not leaking into coolant or oil. And all 4 cylinders seem to be burning the same. Car almost died at the round about again today. As far as I am aware the only thing that could cause pre det and power loss during a head gasket change is if the timing was off.

 

[ald17]

My thoughts exactly mate, car was running sweet before gasket, and nothing involved in gasket should change fueling. Odly enough the car now on occasion seems to suddenly get its performance back, still get the pinking though which wasn't there before, is it possible that the chain tensioner is maybe not holding oil pressure properly now, I guess, plugs look the same but judging the colour of them running lean. But timing and fueling can cause a lean run and nothing that effects fueling was changed on gasket change so again I am back suspecting timing. Tempted to just go to a 17% to reclaim the lost power.

 

[ald17]

Sorry its all good after seeing good compression across the board and finding out it was overfueling on all 4 cylinders I suspected the fuel pressure regulator which turned out to be correct. The performance is back to how it was before I suspect this is what caused the head gasket to blow.