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[CBH]

Hi Mark
Is exhaust noise a sympton of a stuck EGR?
cbh

[kentman99]

I picked up the car from the garage about an hour ago by which time they'd closed. I still haven't found exactly how they arrived at there conclusions re the exhaust valve. After driving the car for only the second time myself (my bro has used it and told me how it was behaving up until this point) it started fine and wasn't particularly noisey even when you revved it up a bit.  The idle was still a bit erratic but didn't cut and only the occasional very tiny misfire. I did notice the power was a bit lacking during the 10 or so miles back and I think speedo may not be working totally accurately. I had a closer look at the exhaust when I got home and to me it looks the cause of throaty noise is the two sections of pipe that run along the bottom of the car from the manifold. They both look very badly corroded and after a while of revving the engine they both were rattling and knocking. I was thinking of taking some photos of that part of the exhaust and wondered if anyone would be kind enough to allow me to email them over to get an experts opinion? The brakes also require attention as I was getting a bit of a grating feel through the pedal plus the didn't respond all that well. And if that wasn't enough I reckon the power steering needs a check over as the steering got stiff when trying to park and also was a bit noisey when on a full lock.  Oh yeah you can't open the drivers from the outside!!!   Apart from that the car is spot on!!!!

[kentman99]

any thoughts guys?

[NiallyV6CDX]

I think by this point we can conclude it is NOT a bent valve, or you wouldn't have got home the other night I dont think. Althoug the EGR valve may well be faulty.
The noise may well be the exhaust blowing/coming to the end of its life. The mid section includes the first set of silencers in the system (the second being the backbox), if the are old they can corrode from the inside out and all the loose damping material can clog up the system, causing considerable back-pressure and thus reduced power. If the were rattling its possible the joints where they are bolted to the downpipes have come loose, or maybe some of the rubber mounting rubber that hold up the mid section have come off, that would explain the wobbling/rattling.
As for the missfire, has anyone checked the condition of the spark plugs and ignition leads?

[kentman99]

That's an interesting slant on things, so if the exhaust valve was faulty it would of made a long motorway journey difficult if not impossible??? The garage only cleaned the breather pipes and cleared the excess oil away and from what I was told there was lots of it. I'll get the plugs and leads changed and see what difference that makes but I was (until reading my last reply) reluctant to mess about changing the exhaust if the valve was the issue. I do have a mate who works for kwik fit who with a bit of luck get it done a bit cheaper for me though i'm assuming it still won't be peanuts. Any ideas on what might be up with the steering?

[kentman99]

Would it be right to assume the exhaust valve is not faulty if I was able to drive a considerable distance on a motorway??

[Andy B]

Would it be right to assume the exhaust valve is not faulty if I was able to drive a considerable distance on a motorway??

Which one of the 12 exhaust valves do you think is bent &, other than say so, why?  :-?  :-?    

[kentman99]

There's more than one then???  Haven't a clue too be honest.  All I know is the garage reckoned my throaty exhaust was down to a broken exhaust valve(s).......ive yet to find out if they pressure tested the head but should get an answer tomorrow.

[HGV mechanic]

There's more than one then???  Haven't a clue too be honest.  All I know is the garage reckoned my throaty exhaust was down to a broken exhaust valve(s).......ive yet to find out if they pressure tested the head but should get an answer tomorrow.

more likly cracked thn bent, pressure test will tell all

[Andy B]

There's more than one then???  Haven't a clue too be honest.  All I know is the garage reckoned my throaty exhaust was down to a broken exhaust valve(s).......ive yet to find out if they pressure tested the head but should get an answer tomorrow.

You drive a V6 24 valve engined car, 12 are inlet and the other 12 are exhaust, ie 2 in & 2 out per cylinder!  

[kentman99]

Is a pressure test the only sure fired way to confirm its the valves?

[NiallyV6CDX]

I honestly think there is nothing wrong with your valves (cylinder head exhaust valves) because if there was your car would be running very badly, not just a bit noisy. The EGR valve (exhaust gas recirculation valve) is the pipe that comes up from the right hand exhaust manifold and joins to the right hand side of the top of the intake manifold, with the black plastic cylinder ontop with wires comining out. It is and emissions reducing feature that introduces exhaust gas back into the intake air to be re-burned. If it was faulty it may cause the engine to idle erratically perhaps, but nothing major and it wouldnt cause missifire or excessive exhaust noise.
A compression is a good idea, as is checking the spark plugs, ignition leads, and the whole exhaust system for signs of wear.
When doing the compression test, if any of the cylinders are compressing lower than they should be, pour a tablespoon of clean engine oil down the sparkplug hole into the cylinder, then re-test (this may cause some temporary blue exhaust smoke when the engine is re-started). If on the re-test the compression improves, then the piston rings/cylinder bores are at fault. if the compression remains low, it is a valve problem.

[NiallyV6CDX]

As for the grinding brakes and PAS issues, check the discs and pads for wear, and renew as necessary. If the pedal is spongy/unresponsive, also check all the hoses for condition/leaks and maybe bleed the system and replace with new fluid, as air in the sytem can cause that spongy/unresponsive feel.
 Check that there is pleanty of fluid in the PAS reservoir, if so, maybe the PAS pump is worn.

[kentman99]

Thanks for that Nially I feel a bit more comfortable getting it taxed now!

[kentman99]

Well ive taxed the car and just hope im not wasting my money.  My wife needed to use it this morning and when she drove off the exhaust really sounded awful. I also noticed some drops of water dripping from the exhaust tail pipe. Does that indicate anything?