[cml271102]

Hi, new to E46 ownership. 2005 318ci. Only owned it a week and the timing chain guides smashed in the engine. After a long weekend on the driveway, we fitted the new timing chain (new chain, guides and hydraulic tensioner). Now, since owned the car has felt slugish (not accelerating as fast as it should, feels like it has no go when you floor it, 2nd gear 30mph should feel it pull like a train, it does not.) Both lambda sensors have thrown up codes, I believe this to be because of the aftermarket exhaust system, this, I think is causing the car to over-fuel/run rich. While doing the timing chain, we of course also changed the rocker cover gasket, we mustn't have fitted it properly, as a few drips leak out every now and then. I've heard this would cause the oil pressure to drop, causing the vanos to throw a wobbly, and make the car sluggish. I'm just wondering if these are valid reasons for this sluggish behaviour. Could I map out the lambda sensor issues?

Thank you very much for reading.
Any help is greatly appreciated.

Cameron

 

[4aceman]

I've heard this would cause the oil pressure to drop, causing the vanos to throw a wobbly, and make the car sluggish.

not from a valve cover leak

What codes are you getting? What are you fuel trims like at idle and when you're driving?

You could try disconnecting the pre-cat O2 sensor and seeing if that helps out. Same thing disconnecting the MAF sensor (just not at the same time..)

 

[e46oil]

My car was gutless and jerky low down before I fixed all the vacuum leaks, didn't perform under 4000rpm, now it pulls from 1000. My cars a 6 cylinder though don't know If yours are as sensitive to it.
I don't think a bigger exhaust would upset it that much, when I got mine the exhaust was blowing badly and it didn't seem to effect it.

 

[4aceman]

when I got mine the exhaust was blowing badly and it didn't seem to effect it

A blow before the pre-cat sensor could let in oxygen tricking it into thinking the engine is running lean. This can cause very rich fuel trims

 

[TobyB]

A convertible 318? that's a lot of weight for a small motor...
I've got an E36 318 compact, and it doesn't really do much
until it's wound out at 4k or so.

t

 

[andrebimmerandre]

I would first check your fuel trims with a scanner, to see what is going on. Also, don't expect them to be really fast. I can't say it for a 318, since I've never owned one, but I own a 316 and yes it is not really fast. Don't get me wrong, they are fast enough to get along with the traffic here, especially if you downshift now and then, but don't expect you're going to blow out everyone around you.

 

[mega_stihl]

This happened right after your timing chain guide problem. Could it be that this issue caused damage to the engine, because the chain might have jumped a tooth?

 

[markusmarkus]

Scan the engine computer (DME in BMWspeak) for codes. I agree with mega-stihl, you may have the cam timing off by a gear tooth.

 

[andrebimmerandre]

This happened right after your timing chain guide problem. Could it be that this issue caused damage to the engine, because the chain might have jumped a tooth?

I'm not 100% sure about this, but I thought these are not interference engines. What can happen with these engines is that the plastic pieces block the oil pump tube, and therefore cause oil starvation.

OP: What is good to check, is your timing. You used the right tools to align the camshafts and crankshaft?

 

[4aceman]

I'm not 100% sure about this, but I thought these are not interference engines.

I don't think any engine made in the last 30 years has been non-interference

 

[mega_stihl]

I don't think any engine made in the last 30 years has been non-interference

Mazda Miata

 

[4aceman]

Mazda Miata

You got me 😆

 

[andrebimmerandre]

I don't think any engine made in the last 30 years has been non-interference

Actually I found a pretty interesting video about this engine:

This is of course not completely scientific, but it shouldn't be an interference one.

 

[4aceman]

Very interesting. I didn’t think non interference engines were as common anymore given the higher compression ratios