Damn CA

So far up to date I've done the following: replaced cats, replaced egr valve, replaced fuel filter, new plugs, seafoam & various injectors cleaners, and bead blasted the plenum clean, re-set timing to 6*BTDC

After putting it back together I'm idling high when in park ~ 1100rpm. I'm thinking vacuum problem... what do you guys think? Which lines would you go for first?

Went to get it smogged again today after it was nice and hot with all the cleaning crap out of the system and my nox was ~ 1800! DAMN!

Things it could be:
none or weak vacuum from egr to solenoid [probable. going to buy this]
defective solenoid [getting new one from gm dealer]
clogged egr (underneath valve) [hoping this isn't the case]
stock chip [in the mail, should be in this week]

I want to rule out the clogged egr, and i hear if I push on the diaphram of the egr when idling and it drops/makes noise then I'm good. Thing is, its hot in there and my finger can't quite reach. What do you guys usually do?

Can you guys think of anything else?

 

Try a screwdriver or some bent metal.

But, yeah, 1800 is high, since you replaced all the correct parts and set base timing. Try doing a cylinder drop test - disconnect the IAC, then disconnect one injector at a time to see if one cylinder is weaker. I'm guessing a vacuum leak near to a few cylinders, or perhaps a few bad injectors. Measure the resistance of each injector (Ohms), and see if they're about 12-15 Ohms. The "performance chip" may also be the bugger, if it has EGR disabled. Any idea what the chip has done to it?

 

I was told by the guy @ tpichips that the ECU should pass smog fine... but I'm going to throw in a stock chip just to be sure

can you give some more details on that cylinder drop test? Do I just pull the electrical connections from each injector? What am I listening for? Plug it back in before going to the next? I haven't pulled the electrical connector before.... dunno if I have to take off runners or tb/plenum for it? Oh, and same gig for testing resistance of the injectors?

 

1800 sounds like a problem with the EGR system to me.
did you hook the EGR vacuum hose up to the port on the TB?
it needs to have vacuum at part throttle, hooking to a non-ported vacuum source won't supply enough vacuum at part throttle.

 

There's a vacuum line from the EGR valve (or solenoid?) to the Throttle Body? Do you mean the plenum? I will post a pic of what I got here... maybe circle what/where you're talking about?

I circled a couple things I have questions about. I'm not 100% I put the vacuum hoses back on correct... can somebody tell me what they are?

 

the hoses on the solenoid look right.

in the third pic, its kind of late here right now & my alarm is more than a little loud when i set it & pisses the neighbors off so i can't look at mine right now, but i believe one of those hoses go to the charcoal canister & the other is for the crankcase breather. i think the one you have the question mark on is for the canister.

the vacuum source for the EGR is on the other side of the TB in pic #3 its on the bottom of the TB & kind of hard to see.
if you have the EGR vacuum hooked to the plenum you won't have enough vacuum to open the valve at part throttle.
if you have a pic of the other side of the TB like pic #3, but taken lower it may show the EGR vacuum
fitting.

 

1100 RPM is a high idle, usually a vacuum leak
a vacuum leak can cause a leak condition
once an engine starts swaying a bit into the lean the NOx sky rockets
fix the high idle first. Squeeze vacuum lines to see if where then are going to are leaking. The old carb cleaner trick, the whole nine yards.

 

I believe the hose in question does route to the
charcoal canister located passenger side corner of
the engine compartment, Id have to double check
my car for confidence.

I see you went ahead and bead-blasted your plenum
like I advised! I believe that's the only way to go when
cleaning it up.. now you're ready to polish it to mirror
finish in your freetime, after emissions of course

 

Hmmm, this is the only one I have handy.

Also, any ideas on which vacuum hoses to check for that high idle while in park?

 

Thanks TPI. I just need to know what hose goes to the right of the MAP sensor on the plenum on the passenger side of the engine. It's in one of the pictures. Any ideas? Right now I have a hose going to it that's from a T-connector. I haven't tracked down where the other 2 lines are going, but the hose is very fraile and needs to be replaced.

 

Denn-Shah is talking about the 2 fittings on the very
end of the plenum right before the distributor plate on
the passenger side, correct? I have A MAF TPI car so the
solenoid might pick vacuum up from a diffrent place than
on my car.. I have one going to the EGR solenoid and the
other routed to the EGR valve underneath my plenum.

To my knowledge, the fittings on the throttlebody route
to the canister and the other to the crankcase breather,
like Denn stated in the previous post

 

the fitting i use for EGR on my motor is around here,
the throttle cam is in the way to see the fitting.

 

Can you post a close-up of the location and hose?
I cant quite spot it, we might have to wait for a MAP
TPI guy

 

Sure, it's in this one

 

i think the hose to the right of your MAP sensor goes to the AIR injection valves.

 

Oh ya, my crankcase breather has tape at the top because it's really cracked. It seemed like a special part, do they sell them at napa/kragen? Would this cause any behaviour im experiencing?

 

Do you have a pic by chance? Does it connect to a T with 2 other vacuum lines? If so then I might have hooked it up correctly. However, those other 2 lines are in bad shape... would they have anything to do with idle or nox?

 

AHA! that's the culprit, I believe MAF TPI cars dont have
that fitting in that location to my recollection, hence the
trouble identifying it.

 

i don't have any pics. i lost my cable to link my camera to my pc.
i think there is a T in the AIR injection vacuum hose to split it off the the 2 AIR injection valve fittings. i'll try to remember to take a look at mine tomorrow.

 

something i just thought about, do you still have the vacuum line diagram under your hood?

 

Nope lost it in a car fire about a year ago

 

TTT

Any info for replacing the crankcase breather?

Also, a confirmation on any of those vacuum lines? I do have one of the ones in question going to the charcoal canister so I think I'm good there. Later today I hope to track down this vacuum leak.

 

damn both napa and kragen say they dont stock the crankcase breather. Any ideas?

 

GM dealership if you have one locally, I call both Pontiac or Chevy dealerships depending on availibility of the part.

 

****. I tried reaching under the EGR and pressing up but nothing is moving.... where exactly is the diaphram and what do you do to move it? I had the car cold and just started it and wanted to test it.......

 

i couldnt pass with any smog equipment, my nox and co's were very high with a gutted cat, i put on a new magnaflow cat, no other emissions equipment and passed here in CT with flying colors

 

I put in 2 fresh cats... wish that had done the trick.

Threw in the stock chip and the car started no probs.... alright! That's a start

Went and tried to squeeze all the vacuum lines I could, didn't notice anything significant.

Sprayed MAF cleaner on my TPS and IAC... thought it would help clean up the terminals.

Sprayed WD40 over the ends of all the hoses I could find and didn't notice anything Any certain technique for this?

 

Took a good pic of those vacuum lines I'm confused about with the T connector. 1 goes to the charcoal canister and the other goes to another 'junction' that has 2 lines. 1 going across the engine bay and i dont know the other. Does this look right?

 

Anyone ever put their hand under the EGR to push on that diaphram? Couldn't get anything to move...

Also, I tried tracking down the vacuum leak. Sprayed WD40 everywhere but didn't notice anything out of the ordinary. Some pointers?