lower intake manifold

I just replaced the lower intake manifold on my 2000 olds silhouette. I put everything back together. I started the car and it is running really rough. The check engine light stays on. When I engage the car to drive it dies. There are fumes coming from the tail pipe. I also replaced the spark plugs while I was there. I put original AC Delco plugs. (expensive)..

What wires could I have missed to cause these symptoms. I connected the coil packs in the right spot and all the ignition wires are in the right spot. ( it was a heck of a time to pull them out)

My guess is either a vacuum leak or a missed sensor wire. Getting the codes scanned should tell you more. Autozone will let you borrow a scan tool for free (MSRP deposit required but fully refundable).

did you keep the pushrods in perfect order. Some are longer than the other by just a little. If you mixed them up it could be your problem.

Yes, I kept the push rods in order and I marked them when I pulled them out. I did not make a mistake putting them back in. Today I scanned the computer for the codes. I got 1635, 5V Ref. "A" Circut.
P0107 - manifold absolute pressure/barometric pressure circiut low Input.
P0203 - Injector circuit Malfunction- cylinder 3.

Any help with these codes would be appreciated.

Which engine? Code refers to no vacuum to map sensor and a problem with connector on #3 injector.

Yes, I kept the push rods in order and I marked them when I pulled them out. I did not make a mistake putting them back in. Today I scanned the computer for the codes. I got 1635, 5V Ref. "A" Circut.
P0107 - manifold absolute pressure/barometric pressure circiut low Input.
P0203 - Injector circuit Malfunction- cylinder 3.

Any help with these codes would be appreciated.

Looks like you may have pinched a harness putting your intake back togather.
First you need to look at the 1635 code because this is the 5v for the MAP sensor.
Check the 5v wire (gray) at the following sensors,TP sensor, MAP sensor and the EGR Valve Pintle Position sensor.
If it is 0 volts, check the wire for a short to ground.

It also sounds like the #3 injector wires are shorted to ground


Which engine? Code refers to no vacuum to map sensor and a problem with connector on #3 injector
This vehicle is only equipped with one engine option.... 3400

Thanks on the engine, GMMerlin, thought the 3800 was available, through me off when he stated replaced lower intake manifold, no reason for that I knew of on a 3400, only the gasket?

I check the voltage going to the map sensor and it is 4.9 V. I checked the voltage going to the TP sensor, it is around 8 V. I made a mistake in the first posting....saying that I changed the manifold.....I changed the manifold gasket. My engine is 3.4 Litre. I scanned for codes again today and I got another code which is P0108. Manifold absolute pressure/barometric pressure circuit high input.

When I excellerate around 4,000 rpms. it seems like the engine is cutting off and it won't go any more past that. You were saying that I could have pinched the MAP sensor connecting wire. Possibly. Originally I put that wire on the side instead of underneath the sensor. That was pretty tight over there. I disconnected it and put it underneath like it was suppose to be. Car is driveable....but after 10 to 15 min the car stalls at the stop light.

Help!!

The rev limiter will cut ou tthe engine in N at 4k, normal. Focus on vacuum to the map sensor and it's wiring.

I took the upper intake manifold off again to check for injector No. 3, that I am getting the fault. I noticed that my lower intake manifold for some reason I put it backwards. 1,3,5 are firing in the front 2,4,6 shows in the back. I dont' know how I could make such a mistake.

Now, all the injectors that are going to the manifold are probably in the wrong firing order. I wonder if I could leave the manifold where it is and reroute the injectors. If I have to take the manifold off and turn it 180 degrees, would I have to change the gasket again?

All the wiring seems to have current flowing except one that goes to the little box, where the hose to the PCV valve is connected. There is no current there.

Quick response would be appreciated.


:banghead:

Okay, I found what my problem was....got the car running....

No codes show up.

My message centre flashes.....SECURITY......any ideas how to reset it?