So last week on my way home, I floored the gas going up a hill, and out of no where complete loss of power. The car was barely moving and completely misfiring, the restricted performance / check engine light came on. just two blocks later the car shut off. I tried starting it it fired up but its completely misfiring.

I towed it to the dealer as they only charge $170 for a diagnosis. Today I get a call from them stating that they don't know what is wrong, they want to take the valve covers off, the oil pan and do a compression test. all for the amount of $1400. The service advisor educated guess is that the lower tensioners gave out since the top had been done. He said that the cylinders on the back of the engine are misfiring based on the codes its throwing out. I am thinking that I should tow it to an independent shop and get a second opinion. $1400 just to tell me whats wrong with it seems steep to me. Just thinking of a $1400 diagnosis plus whatever is wrong on top has me really worried.

Anyone know of a good independent shop in the west los angeles area? I know I am not giving enough technical details for any of you more experienced owners to try and help with a diagnosis. Unfortunately the dealer was not able to give me anything to go by aside from a "give us $1400 and maybe we will know whats wrong". They did say that they ruled out any exterior thing and think the failure is mechanical

The only thing I did different from the year and a half I have owned the car is I put in a can of the BG44 injector cleaner just days before this happened with a full tank of gas, but I doubt that would cause such failure.

Any suggestions out there?

Thank you,

 

Could you give them a call and retrieve the codes they pulled? It could be a lean misfire, ignition misfire, or misfire resulting from mechanical failure. It does sound timing related based on what they have told you thus far but an optimist could say the bg44 shedded a clot in the fuel system, ultimately hemorrhaging somewhere and your being starved for fuel causing a lean misfire. For $170 they should at least provide you with the codes and then we could all help a little more

 

Doing that operation should be less than that for sure - removing the valve covers was 800 at my shop in Nor Cal, and changing the oil pan gasket is very cheap on this car. They may be right in the cause of the problem (which will be comedy expensive to fix as you have to take the whole front of the car and engine apart just to change the guides and lower tensioners), but I am 100% sure than an experienced specialist indie in So Cal would do it for cheaper to do the diagnosis (and the work itself if it is lower tensioners/guides)

 

From all the information I have read on the forum, the failure of the lower tensioners is going to result in chain rattle, not skipped teeth and timing problem. There were a couple of reports of 3rd gen tensioner failure so that can't be ruled out.

R&R of the cam covers is at most four hours for a novice, more likely two for experienced mechanic. I hope someone can steer you to an independent as the dealers tend to through parts at cars and see what happens.

 

I towed the car from the Dealer to an independent shop today. When I picked it up they gave me the codes the car is throwing

it says 102165 SDD test found P0300 - P0305 - P0306 - P0307 - P0308. Checked fuel pressure found OK

They also managed to damage my front bumper as they towed the car with their electric hoist, failed to put the screws back on the engine plug covers

 

That sounds like the secondary timing chain on the passenger side! So, why do you think the tensioners were already done?

BTW, don't worry, the snake oil did not do this. It won't do much of anything when diluted like the instructions say!

EDIT** I meant DRIVER'S SIDE!

 

I have all the car's service history as I bought to from the original owner. I have the service record from the dealer for the timing chain tensioners

 

Irrespective: secondary tensioner failure

 

I meant Driver's side in post #6!

It will be interesting to know if the 3rd gen tensioners were in there. The metal tensioners on my XJ8 (factory) showed little wear of any kind at 125,000 miles.

I wish I could think of some other root cause besides a timing chain, but I am afraid it does not look good, my friend.

 

Secondary chain broken? You need to get that valve cover off and not try to start the engine. If it's just a failed tensioner you may not have damaged the valves.

 

In my personal experience with these engines and failed tensioners, roughly anything over 1500 rpm will bend the valves. If the tensioner fails just after starting (or attempting to) in the morning, chances are that it'll be ok. We had a customer that was going about 45-50 in OD and sport mode off that broke a tensioner and it didn't bend valves. If he floored the accelerator (according to the original post) and then lost power, it's quite certain that it's toast. It's sucks to hear of these stories because I've seen some pretty nice cars go parts heaven due to the excessive cost to repair.

 

All might not be lost, if those codes were grabbed with the engine running, you might be off one cog -- replace tensioner, should be ok.

Back about a year ago, a XK8 owner has the same issue (same codes): we all were sure it was tensioners, but turned out to be dirty coils one side (or so he reported)

 

Hmmh!

 

My money is on one of two things:
1. the tensioners that were replaced were 2nd gen and still prone to failure.
2. Excessive oil in the plug wells

 

Ignition primary winding common signal for the driver's side bank of coils could be compromised. If I recall, all four on each side come to a single point in the harness, different for each side - see blue circles in pictures from electrical diagram.

One of those two connections could have failed - I don't know which is passenger or driver's side - but they each have two connections that can fail - one shown in the right in the 2nd pic below and the other over to the left at the engine control module in the same pic.

A failure of either of these connections OR a failure in the engine control module (less likely) will cause your exact symptoms.

Can't promise that it's NOT a timing slip in a cam sprocket... but this should be checked first! jhartz could be close - not dirty coils, but a dirty coil connection?

Good Luck!

 

Well I am sad to report that the timing chain snapped on the drivers side bank.

I will await the results of the compression test and hope for the best.

Thanks for all of the replies

 

Update:

I got the call this morning, and there is no compression on cylinder #1

Shop is quoting me $6200 to fix. Thats taking the head off fixing the valve etc..

I am at a crossroads here as my cat is in pristine condition aside from its current problem, but i really don't know if its worth it to fix...

 

Bummer... Sorry about your loss!

BTW, where are you going to get another vehicle in such condition, with such class and style and that is so wonderful to own and drive for only $6k?

 

Sorry to hear about that.

Just my 2 cents... If it's pristine, then it's worth saving. Yeah, $6200 towards another car is a good chunk of change, but if you sell it, you won't get much for it and could end up going nowhere other than somebody's back yard forever unless they're skilled technicians with some time to work on it. And if you do fix it, it'll have the latest metal head gaskets, new chains and seals.

 

Gutted for you VR6Guru, the worst possible outcome. I risk the wrath of the forum here but $6k+ for a head job/tensioner change seems a tad excessive to me, might be worth getting another quote or two.....?