Hey guys,

Bought a warrantied '05 coupe (6-speed) from a GMC dealer, here in Canada - it's covered for the next three months by their Optimum warranty, which is about as close to bumper-to-bumper as one will get on a seven year old car. The car received a highly detailed inspection, which it passed with flying colours; all it appears to have a problem with are wearing-out tires and this apparent tappet noise and possibly related minor issues.

The good news? The car has only 21,000 KM's - only 13,000 miles in seven years. Remarkably low. During much of this time, I have to surmise from the shockingly low mileage on the odometer (which was verified true) that the car wasn't driven much at all. The car still smells new. The paint is close to immaculate. The engine is virtually spotless. The car drives very, very well. Overall, I have little to complain about.

That said, to the complaint(s)!

Now, my father (who also posts on these boards) has an '04 with twice the mileage of my car, but his motor is whisper-quiet. My motor, by comparison, is noticeably 'ticky' at idle, and loud enough below 3000 RPM to be noticeable (mostly between 2500-3000 RPM). Interestingly enough, the ticking cannot be heard above about 3K RPM, but that may simply be because engine noise in general drowns it out! Needless to say, on a low mileage motor, and with Benz block at that, I expect something quieter than my '81 DeLorean, and yet the Crossfire isn't. It's not abominably loud, but it's noticeably louder than a block of this quality and mileage should be.

My best guess as to the tappet noise (if that's what it is) is due to stuck/seized/goopy lifters as a result of the car being subjected to prolonged periods of sitting around, and therefore lengthy stretches of time within which no oil was being passed through the lifters, permitting them (I'm gonna be technical here) to 'crap out'. To my mind, if that's the case, I take it I should be telling GM to replace the lifters.

On a possibly related problem, I appear to be having an intermittent missing problem at idle (not too rough, though), and the car shuts down rather roughly as well - a bit of vibration, if you will, when the ignition is turned off.

I'm pretty good mechanically, but really only with old tech; my DeLorean, which I've mechanically worked on in great detail, is a simplistic old SOHC V6 without any lifters whatsoever, and my previous cars were all old push-rod V8's (mostly Corvettes). I'm a little out of my league on a relatively 'new technology' German engine, so my guesses are just that - guesses - and I would appreciate any guidance that you guys can share.

If anyone can nod in agreement at my guess, tell me I'm more than likely wrong, or suggest that the idle/shut-down/ticking are related, please let me know. The car is heading to the GMC dealership this Wednesday for servicing, and I'd like to go fore-armed with as much knowledge as possible, as I'm willing to wager that few (if any) of their techs have ever worked on a Crossfire, certified and professional though they may be.

Cheers.

 

Welcome to the Forum and congrats on what seems to be a really nice car.

Great description but it may be difficult for us to help with the diagnosis without actually hearing it. You could try to post a video with sound and that may help out. Reason I say this is that these cars actually have a common ticking noise (many mercedes do). Some will say it might be the fuel injectors. Others may have other thoughts. I have the "tick, tick" noice too, but usually you can only hear it appreciably at low idle and / or when the hood is open. What side of the engine is it coming from? I've identified the noise from the drivers side near the wheel well fender area.

As far as the miss.........no pun intended but it will be a hit or miss diagnosis. Lot's could be causing that, even a loose vacumn hose.......... but, you should do a search on here for similar symptoms and see what pops up.

The hard shut down also seems to be common. I'd have to say mine does that too, but it's only hard by my standards, I don't think anyone else might notice it or say it they feel it. It's just something I notice in comparison to my other cars. May not be anything to worry about on this issue.

Good luck with everything. One word of warning though, if you are taking it to a GM dealer, I'd be very warry of them being able to work on these cars. Heck, I even have my worries with certified Crossfire mechanics. I haven't found any that are all that good.............

 

Caution on the dealer, was good advise, warranty yes, good mechanics doing the work, no. AS mentioned above, a lot of things can cause the problems you described. I am completely sure, it isn't a "tappet" noise you are hearing with a 13k mile car. Rough idle, do the throttle reset a few times, this is easy and hate to say it, but the crankshaft position sensors will cause rough idle, rough lower rpms. A vacuum leak will cause the same symtoms, so check all the hoses. Throttle bodies have been known to have vacuum leak around the base... There are several threads on here dealing with all these problems. Good luck on your search.

 

Clutching at straws with this guess, could you have a fault on a plug or cable and you can hear the spark? I had it once on a car, I saw the spark when it got dark. The spark had burnt a track on the cable, it looked like a firework display at night. Car seemed to run fine, which was the opposite of what I would have thought.

Maybe one or more of the plug covers are not on all the way.

 

DMC81 can you talk a little bit about your choice of the black limited instead of the blue SRT-6 please ?

 

Thanks for the tips guys; I figured it would be a case of several possibilities. Tappet noise from cruddy lifters was the simplest guess - I do know that they can go 'off' after prolonged periods of sitting, and so even at low mileage, it's possible to have it making a bit of a racket. Interesting thoughts on the other ideas.

I'm a little concerned about GM taking care of it, too, but they did mention that they'd send it to the local Chrysler dealer if they couldn't figure it out... heck, maybe I should tell them to take it to the local Mercedes dealer, at this rate.

I'll add a link to a video I took of the noise (at the bottom of my post); I took the video with my iPhone 4, at operating temperature (it had been driving for a couple of hours straight).

As to why I went with the non-SRT-6, it came down to the simple fact that this car had about 1/6th the mileage, and as I was looking for a daily driver, and one that would preferably last for many years to come, I wanted to have as 'new' a car as possible. This car has 21,000 KM's, the other had nearly 120,000KMS. For all intents and purposes, this car that I bought is indeed in 'almost new' condition (it even smells new, inside), despite these relatively minor issues.

Link to my cruddy iphone video (the ticking is fairly evident... from the sound, I almost want to guess exhaust manifold, now!): IMG 05031 - YouTube

 

Sounds kinda like exhaust to me from the video. The 'tick' is different than a lifter tick would sound like. More like manifold leak. Check around the exhaust ports on the manifolds. If you see a spot of black soot that means you have a leak right there. If this is indeed the case do not simply tighten the manifold bolts harder to try to stop yhe leak. You can check to be sure they are torqued properly, but never overtighten the manifold bolts to try to stop a leak. Gasket replacement is the only good route to take.

 

Yeah, after listening to the video, it does sort of sound like an exhaust manifold gasket has gone; is that common in these cars? Could still be the tappets, but... eh.

Any other thoughts are appreciated. Thanks again guys.

 

sounds like injectors firing to me.... You see what you get? LOL..... If it has set for awhile, why not have them change the fuel filter, run some injector cleaner thru it, and make sure everything is good with the throttle body...clean and such... Look at all the vacuum hoses as well

 

... injectors? No kidding! I don't disbelieve the possibility, but I've never heard of fuel injectors being so noisy, though that may just be my lack of familiarity with modern engines shining through. I'm only 30, but most of my cars have been older than I am (mostly Corvettes).

I've heard that most 'stick it in the gas tank and drive like hell' fuel injector cleaners aren't even that good, and I have a hard time imagining that anything short of a professional cleaning would help if the noise really is due to dirty injetors, but again, that could be my lack of experience with modern engine blocks doing the talking.

I think I'll take the suggestions of valve train noise, exhaust manifold leak, and noisy injectors to the GMC dealership when it goes in on Wednesday, and see what they come up with. If anyone has anything else to add, let me know! Thanks!

 

Hey guys.

Just a quick update, in case anybody was curious, the problem turned out to be lifters - as in they were pretty much shot. The lifter leakdown was bad enough to cause some of the valves to not open fuly, resulting in the miss, and the rampant ticking noise.

The cause? Weill, with only 20,000 kilometers on the odometer in seven years, the Mercedes mechanic that initially diagnosed the problem stated that the lifters simply sat 'disused' (i.e. not lubricated) for far too long, causing them to seize.

There is zero structural damage inside the engine from this, but the noise was getting very annoying... thank goodness for warranties, I wouldn't want to 'out of pocket' pay for this. I'm familiar with old-style SOHC & pushrod engines, so I was never entirely sure about what was causing this problem - I've only worked with solid lifters in the past. It's good to finally have it sorted out.

Thanks again to those of you who tried to help, and if anyone encounters a similiar noise with their car later on, maybe this thread will help you diagnose it!

 

For the noisey ignition shut down. Push the clutch and should solve the prob.