I had to replace the water outlet connector on my 2001 Intrepid, which has a 2.7 engine. This job involves removing the top half of the intake manifold, replacing the water outlet connector, and then putting it all back together.

I also pulled the crank damper off and replaced the front crank seal, and put that all back together.

I thought the job went well, but when I start the engine, it immediately wants to rev to 3500 rpm. All the manifold connectors are tight. The EGR tubes are seated. I removed both throttle cables to check if one was bound, but the same problem still happens. I had replaced the PCV valve, and I had found the vent hose disintegrating, so the PCV valve is installed but not hooked to the vent hose, I put tape over the port and am planning to get a vent hose for that tomorrow. I checked the TB throttle blade with a mirror and it appears to be pretty much shut tight.

I've done this same job once before and hadn't had any problems that time. I've run out of ideas on what might be causing this.

Suggestions?

 

Can you hear any sucking downline of the throttle plate? It reminds me of when I took out the idel air motor to clean the port on my truck. You may find a air plenum leak or intake manifold leak.

 

Well, long story short, the problem was a vacuum leak. Must have been a fairly severe one. The long story I underwent involved detailing the throttle body-looks brand new now, fixing or blanking off all vacuum hoses, and meticulously cleaning the upper and lower intake manifolds mating surfaces. And none of that helped. So I went and got a new set of the high temp silicone seals for the manifold EGR ports, and a set of plenum seals that go between the upper and lower manifolds. Note that the factory service manual says you can continue to reuse the plenum seals as long as they aren't torn or show other damage.

Problem fixed. I think it was the plenum seals. Actually, they don't cost much, so it's worth it to save the hassle and wear and tear and just swap those out whenever the manifold gets separated.

Car's running great now. A newly cleaned TB probably doesn't hurt, either.