You can drill small holes in the blades.
Did you check opti harness plug. Some of your symptoms are pointing toward ignition too, even though I know you just replaced the Opti, it doesnt take much for an opti to be out of whack.

 

before drilling you might want to try adjusting min air screw until you see around 30 cts. (car running) on data master, shut car off restart, this will reset tps. and recheck iac cts. tweak more if needed (this is the fastest and easiest way to adjust the IAC/counts, but scan or daamaster is needed). By openimg the tb blade you will also lower the tps volts. Yours should end up right around.6mv., this should improve the symptoms you described. Oil from the dip stick could be clogged pcv, test pcv, the above air control may help the meterd air side of valve cover return.

 

Where is the min. air screw on a LT1?

 

Problem maybe, I turned the TPS towards the rear and the voltage went up, turned it toward the fron and they went down.
I thought if you turned it toward the rear it was supposed to go down?

 

On the drivers side, at the top next to the upper attaching bolt you should see a set of threads that are touching the throttle body cam stop at the top of the cam. The screw will have to be accessed from the side, and it runs parralel to the upper attaching bolt (you won't see the head of it). and most probaly wil require a small torx head.

 

Oil out the dipstick should not happen I would do a leak down test on the moter to rule out mechanical problems

 

Randy I agree 100%. oil out of the dipstick in NG. first check your oil level and make sure its not overfull and doesn't smell of fuel. Make sure its not milky also. If there is fuel in the oil check the FPR vac hose to see if fuel is going in the engine through the diaphragm of the regulator. If its milky, take 10 steps backwards and punt. If its clean oil, and not overfilled, you would be getting blowby, remove the pcv when hot and see if its smoking out of the crankcase. No smoke check the pcv and the hose for proper vac. Maybe its clogged. If still nothing pull the plugs and do a leakdown test. If you need to borrow a tester let me know I will let you borrow ours.

 

Thanks Jon, I just changed the oil a week ago and it smelled of gas. I reset the IAC as per FSM and it was sitting at 1 5/8", instead of 1 1/8, but the Datamaster could not connect to the ECM, so I do not know if that helped yet. I am going to pull the pcv in the am and check that and I am not looking forward to the leakdown test, as the car has 175k miles and I am betting w/my luck I will have a blown head gasket.
I am getting good at tearing the car apart and putting it back together,
thanks for the offer, I will let you know after tomorrow what is happening.

And thanks everyone else!!

 

One last thing, when I pulled the TB today, a couple of the bolts holding the TB on had oil on them. And the inside of the intake was solid w/dried oil. It was a thin layer, not sure if that is normal or not.

 

Sorry to jump in because I'm not fluent in EEC/EFI, but a few things strike me from a purely mechanical aspect.

Oil up & out of dip stick tube usually says that the crankcase is under pressure. PCV system is where to start. Then to other places(mechanical ones) that could presurize the CC.

Large miss above 3100, not at idle? Ignition sys, fuel injectors & pres. reg.

Gas smell in oil, for sure it got there either thru the injectors or the pres. reg. or both.

Have you tried to use a vacuum gauge on the motor at idle to "see" what's going on.....I use this link.

http://www.secondchancegarage.com/public/186.cfm

I use this as a refresher every yr when I do my summer get ready. I know it's old school, but that's where my level of knowledge is as I've said I'm not good with all this electronic stuff. One thing, heated O2's should be fairly steady on cross counts @ C Loop, and have fast moving Millivolt readings, if the M/V's are slow the O2's are lazy & need r&r'ing....that I learned from my LT5.

If it wasn't a computer controlled FI motor, I'd use the vac gauge to tell me, late ing timming, valve guides worn, valve seats burned, rings bad, ya know all the mechanical things that can go wrong that show up on a vac gauge...oh, forgot a vac gauge can also tell you if the timming chain is okay. I'm not trying to say it's the "end all, be all", it just points to areas to look at from a mechanical aspect.

Sorry to stick my nose in, not trying to be a wise guy. It just seems to me that there maybe some mechanical issues causing strange data on your scanner. My apologies.:o


Tom

The oil you found in the plenum & T/B is some what normal....but if you saw puddling then for sure something is over presurizing the CC. I forgot this also, how's your EGR? I forget that thing because my LT5 doen't have one.

 

Checked my oil, I am a little over filled. Fuel reg. is only a year old and I am on my 2nd set of FI's. How do you check a for a bad fuel reg?
And does it matter which vacuum port you hook the reg. up to?
There are 2 right on top of each other, just wondering if I have it hooked up to the wrong one or if it matters.

 

Can't help much with which port for the regulator, I could look in my 90 FSM but I doubt it would help? I doubt that it matters as long as it gets constant manifold vacuum though.

If there is fuel in the regulator's vac hose that is one sign, I know that for sure. I could look up the test flow chart in my FSM? I seem to remember pionching off the return line w/a fuel pres gauge attached to the rail connection and watching the gauge for a PSI rise...but that's all off the top of my head.


Tom

 

randy check the fp with a gauge.. it should be 40 at idle hose on. remove hose 43.5 +- if you don't have a gauge.. get one. if the reg is good check pressure while running, shut off with gauge on and see if it goes down and how fast. is it hard starting? also take the hose off and see if fuel comes out of the reg while running. the vac hose has to go to a manifold fitting directly
jon

 

I have been trying to track down another problem. When I turn the engine off the FP drops pretty fast, always thought it was a bad FP or the pulse dampner.

 

fuel is getting in the oil have you checked the evap canister. see if it has fuel in it, the vac hose on it can also suck up fuel sometimes. I would concentrate on that problem first. Is there a lot of pressure in your tank when you remove the cap after a long drive?

 

Don't know about the pressure, I have noticed sometimes when I fill up there is a lot of pressure and sometimes none. Just never paid attention to when this happens.
Well I have to take the rear bumper off anyway, got hit by an uninsured driver, so I guess this is as good a time as any to fix the SMC and check the canister.

 

From another forum:

>Find a shop, with either a Tech 2 scan tool, or a digital storage oscilloscope.
Have them monitor the low resolution signal.
If this signal drops out, it defaults, thereby increasing the idle.
IAC can also be controlled, and monitored, however, you may find that the IAC is being commanded higher by the PCM, as a result of the missing signal.<

Missfire sends to much air to O2 sensors and PCM compensates with more fuel then you have a never ending story.

Kjell

 

Ok, got the TPS down to .57 volts and IAC is 63. FP is 40-1 w/vacuum and 43-44 without.
Like I stated earlier, when I changed the plugs the car ran smooth as silk for a couple of days then went back to the way it is now.

Jon, oil is nice and black and the exhaust doesn't smell like gas anymore, know that is not the right way to check, but it was noticable.

Though the BPW on Datamaster is still off on one side, I had a bad connection in one o2 and now it works good.

I did see some arcing last night from the SP wires, they are not even 6 mths old. I suspect one or two are laying against metal, that is my now on my list of things to check.

 

Jon, I have a question. Should I check for fuel in the canister, after the engine is hot or just after it has run a little?

 

Ok, found out a couple of things.
1) for some reason the spark plug socket is binding in 2 cylinders, 4 @ 8
Had to use a different socket to tighten completely, funny that the socket worked on all the others.

2) I pinched a plug wire on the drivers side putting the WP back on, car is running better. But, is not running great, I can still hear a miss on the drivers side, pass. side sounds good.

Funny thing about the 2 loose plugs, I couldn't tell 8 was loose, but 4 vibrated all over the place and the car ran real good at times.