SOHC intake gasket replacement gone wrong - HELP!

I replaced the upper/lower intake gaskets on my '97 SOHC V6 Explorer today since I had been getting the usual warmup problems on cold mornings. The procedure had already been performed several years ago along with the timing chain tensioners.

The gasket replacement seemed to go smoothly, but now the car won't idle for more than 20 seconds. I triple-checked all vacuum and electrical connections and the battery was disconnected while I performed the work. I was very careful to get all the mating surfaces clean and to tighten things evenly. The IAC valve is new and is plugged in.

I installed the gaskets dry, since I couldn't find any info otherwise, but I did notice that the upper gasket I removed had been packed with white grease. The original lowers were coated with oil, which I presume came from the intake.

Should I have coated any of the gaskets with grease, or do they get installed dry? Any other suggestions??

Bob

Reply to
Robert Kuimelis
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There is no need to use anything on the gaskets when installing them. Hopefully, your problem may lie in the coil tower assignments...... When it stalls, does it shut down as if the key was turned off or does it sputter to a lengthy death?

Reply to
Jim Warman

Glad to hear that the gaskets don't need anything on them! When it stalls it sputters to a painful death as the rpms drop lower and lower. I can goose the throttle to keep it going or hold it at about 2k rpm without issue, but there is definitely a misfire/rough running at all rpms even after it's warmed up. Seems to behave like it has a large vacuum leak or > today since I had been getting the usual warmup problems on cold

Reply to
Robert Kuimelis

All PCV valves are not created equal... there is generally an orofice in the valve that still allows flow at idle and other high vacuum circumstances. I don't think it would cause a stall condition but it certainly wouldn't help, either.

Additionally, recheck to be sure that the hoses to the DPFE haven't inadvertently been revered and that the same applies to the hoses to the regulator (EVRV). Also that the EGR valve isn't getting straight vacuum...

Sometimes, it's the simplest things that can screw us up the most.

Reply to
Jim Warman

I've been told that the lower intake might have a R and L side, although it could bolt up in both directions. Jim, do you know if this is the case? Since I removed it on day one and reinstalled it on day two, I don't recall if it went back together in the original orientation. If the ports are not symmetrical, I could imagine major sealing issues between the lower/upper intake pieces. I remember some locating pins on the lower intake, and things seemed to go together properly, but since it's difficult to inspect when it's bolted up I'm left wondering. Comments before I rip it out (ARGH!) to inspect?

Bob

Reply to
Robert Kuimelis

I recall motors where which side up matters and I recall motors where side for side matters (go back to GMs decision to use two different 3.8s years ago and there's a whole different something matters)... unfortunately, the '97 WSM isn't enough to joggle my memory. If someone that is recently familiar doesn't reply, you may need a quick trip to the parts store to compare the two sides....

Reply to
Jim Warman

Mission accomplished! I don't know what did it in the end, but the process of checking continuity of the new ignition wires, installation of the proper PCV valve and also a new intake bellows for good measure made everything right. Could have been a combination of small effects or perhaps a plug wire that was not fully seated. At any rate, it's running well at this point. Thanks for all the help!

Bob

Reply to
Robert Kuimelis

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