93 eurovan emission

[franktalk]

won't pass. too much hidrocarbons. standard 2.4 vs. mine @ 2.86. new cat convert, plugs, wires, air filt, cap, rotor. i hear what may be vacuum leak from top of engine, however cannot locate leak. anyone heard of leaking, pitted cyl heads on this 5 cyl engine? thanks for any ideas? 145, 110, 140, 140, 140 compression. frank in oregon

[veedubmechanic]

Originally Posted by franktalk

145, 110, 140, 140, 140 compression. frank in oregon

looks like your head gasket blew... or piston ring is bad

[franktalk]

howdy vwguy. thanks for the info. I'll check out head gasget and rings. I've driven audi's for many years and am very familiar with the 5 cyl engine. I had an 84 5000 with similar compression numbers and drove it that way for almost 100k miles until a hose burst and blew the head gasget. It was at just over 250k miles by then. There had been no gasget leak or ring problem until then. After head rebuild (no rings), it went another 100k miles before I gave it away.

Could the hissing sound which seems to be coming from under the intake manifold be related to a head gasget problem. I thought it was some kind of vacuum leak.

I've also noticed that more than a few I've 93-95 eurovans I've checked out seem to have top end rebuilds & rings around 150k miles. In audi's, 250k miles is not unusual mileage before the head gives out. Is around 150k miles about the right number for a head rebuild on a Eurovan. My vehicle has 149k miles on it.

thanks again, really a lot for taking your time.

frank in oregon

[franktalk]

howdy vwguy. it's not compression or head gasget. checked these out. Most likely vacuum.

Are you familiar with possible vacuum problems associated with intake manifold or something in or around intake manifold. I hear what sounds like a vacuum leak in that area, perhaps under the intake manifold which of course is not visible.

thanks again, really a lot for taking your time.

frank in oregon[/quote]

[veedubmechanic]

i would say more compression due to the numbers. did you try recheck with oil in that cylinder to see if comp# rose?

intake manifold is problably leaking at 150k miles (plastic intake manifold on eurovan??) I havent seen one in the shop for over 2yrs..

[franktalk]

thanks. plastic intake manifold?????? that's crazy. but its failure would explain the hissing vacuum sound. Can the intake manifold be repaired or is replacement the only option? thanks again. frank

[veedubmechanic]

well if its cracked you could try some epoxy and it should hold for some time, but you dont know it the manifold is even cracked. the intake pipe does make a hissing noise on these though due to the design of it.

[41mag]

heydude! didnt you say hc was high? what about co(carbon monoxide)? usually if one is lean(vac. leak) co runs high. did you check to see if the eng. is skipping on the cyl. with low comp.? what about oxy. sensor? timing?
just some ideas.... 41mag