1995 Ciera Rough Idle possible vacum issues

[nakedeye]

I was messing around and replaced the spark plgus and the air filter. After that, I had a rough idle and some hard "poofs" out of the tail pipe.

I noticed the hose to the vacum pump was shot so i replaced that. Then I poked around furthur and decided to replace the pcv valve and all the rubber gromits and hoses associated. turns out the hose going from the "T" connector goes around the back of the engine and into a sensor. that was completly rotted away and disconected. I figure i knocked it off changing the plugs.

Anyway with all that done, I can't seem to find that "T" connector at pep boys. Any idea on the part number? It is running much better now, but it still happens a bit. That "T" part is cracked on both sides, and very loose going into the engine.


TIA

[3100MPFI]

When you say T CONNECTOR, are you referring to the pipe that goes from the PCV VALVE to the top of the THROTTLE BODY, and then back to the CANISTER PURGE?

If that is the T you are referring too, then I think you are either going to have to go to a DEALER, or a JUNKYARD. I bought one new from the dealer for my Cutlass Supreme for only $20.00.

I don't remember the part number off hand.

[nakedeye]

Yes I belive that is the one. I am slighty unshure about the throtle body however. Not realy shure if I have one, but I did look for a feul rail and did not see one, so I guess thats it then huh?

The T is only about an inch long and the bottom goes into the engine. Off of it are two hard plastic hoses, the larger one goes up front to the pcv valve, and the smaller one wrapes around back the engine into some sort of sensor.

[nakedeye]

okay poking around autozone website I can tell you that the part in question conntects the PCV valve to the evap canister purge sol vlv, and plugs into the top of the intake manafold.

If this does not fix my issue, where should i head next? I have a digital EGR, so I'm not so shure about that going bad if there is no service eng soon light. If I disconnect the wire harness to it and it lights up.

I'm thinking my tps sensor, but I'm not so shure. Again no codes popping out.

I do have some oil backing out of the screen on the throtle body. I'm chalking it up to the enginge "poping." Perhaps that unit is bad?

Agian I'm thrown because there are no codes poping out.

[nakedeye]

Okay. I have repalced all the vacum hose lines and gromets. It seems to have brought it down a bit , but it is still prevelant. When I let off the brake the car stutters forward. If I give it a SMIDGE of gass it gets real rough, then a bit more gas, it seems to lurch forward.

Any ideas?

[nakedeye]

One more bit of info.

When engine is dead cold, and it drops to idle speed just after start, it is much worse till the engine wams up juat a bit (45 sec later)

Nobody has any ideas?

[nakedeye]

Okay so I know I'm only realy talikng to myself here, but I think I've got it down.

The throttle body assembly had some oil leaking out of it when I changed the air filter. I think the pcv was so garbled, that it was letting oil drip down into the assembly. When I changed the air filter, it began to let the system breath right...almost.

I think the little bit of oil in there was making it sputter. I wiped it out, took out the mesh screen, soaked up the oil in it, and reasembled.

I took off the MAF and it looked okay. I re-tightened all the connections on the TPS and IAC and jiggled the arm on the TPS.

95% of the problem is gone now. I'm going to see if I can get to the IAC and clean it a bit. It seems rather dificult to get to it short of taking off the entire TB, but I'll give it a shot.

[Blue Bowtie]

Soak the two mounting screws in penetrating oil, move the lines and wiring out of the way, and you should be able to barely get a Torx bit in there to remove the IAC. It's tight, but possible. I've done it many times on the 191 V-6s.

[nakedeye]

Ok so a bit of a puase for a bit as my first baby came last sunday!!!


Okay so here we are at.

I took apart the entire TB and cleaned it all out. Replaced the IAC and TPS.

There was so much oil and gunk in the TB it was amazing. After I put it all back, it runs a bit better, but after a bit it comes back. Oil will somehowe end up in the TB asembly again and agian. Is the rough idle a backfire???

where the TB mounts to the engine, there is a small hole with a rubber hose going out of the block. This was gummed up. I went through 2 1/2 cans of gum out spraying the entire TB out and inside the engine intake where the oil was. I realy wonder where the oil is comming from and if it's a symptom rather that the problem...

I put bosch plat +4 plugs in there. Is it possible they are just too damn hot and cause an early ignite?

Or I wonder is my backpreasure too high from a bad cat and thats causing this???

Again TIA

[3100MPFI]

bosch plugs are probably the biggest part of your problem. Throw them in the trash and get some delco's (stock, or rapidfires). Do NOT get platinum (even if they recommend it). Just stick cheap delcos in there.

Bosch plugs do not like the WASTE-SPARK DIS system in the chevy engines. We burn the platinum right out of them.

Replace the plugs, and see if that helps.

[nakedeye]

Thank you. I'll try that and give it a shot!

Wouldn't that be funny. 100+ bucks later and many hours of frustration to get to there if thats the problem? LOL