Blue Smoke

[FULLPWR]

Originally Posted by scottfab

I forgot to mention, before I did the bellows How To I tried using a single 1/4 wire insert in 1997. It worked ok but had the unfortunate side effect of causing an uneven look to the bellows. That is why I went with the 0.10 thick sheet of aluminum

Scott, did you make any extras, you may want to sell ????


Luis

[FULLPWR]

Originally Posted by tomtom72

Luis, you could loosen the screws that hold the TPS and move it till you get 0.54volts at hot idle....on my 90 the TPS has slots that allow for some adjustment once the hold down screws are loose.

On the IAC, I don't have my FSM handy. I know there is a "learn" process that it goes thru, but beyond that I don't know much. I never had the need to replace mine. You know the passage for the IAC could be just dirty. Last week I pulled the IAC and used some throttle body cleaner on a paper towel to clean that passage. Maybe just try that for starters?

I'll go get my FSM and look up the IAC. I'll post back at lunch break.

cool ill go do that right now thanks man

[FULLPWR]

here's the IAC i just pulled out

[tomtom72]

Now that is just fugly Luis! Clean that up and clean the passage. Use throttle body cleaner, do not use carb cleaner. I hate to say this but you may have to dismount the T/B and clean the IAC passages using the spray also.

ONE VERY IMPORTANT ISSUE: inside or behind the three blades is a blackish substance that surrounds each blade's hole, that is called DAG....DO NOT mess with that stuff. Leave it alone as it forms the seal when the blades are closed so that the IAC can do it's job. Do NOT use carb cleaner, only T/Body cleaner. When you wipe out the bores just be gentle around the DAG. I just held my T/B up and sprayed the chit outta of it and let all the dirt run out. I used one of my old microfiber towels to wipe up the interior of the throttle body, very light pressure on the rag. I must have used up at least three cans of cleaner.

On the new IAC, just put it in and connect the electrical connector and the ECM does the rest...or it should anyway. According the FSM the only time you need to do anything to the IAC is if you pull it's connector when the motor is running. Then there is a procedure to follow to make it work correctly.


Tom

[FULLPWR]

Tom... your an ACE

thanks so much

Im going to clean up what i can reach, install the new valve so i can get her home. then hopefully r/r the T/B.

my first air duct form didnt fit to well, trying again

Luis

[FULLPWR]

changed out the ngk's and put in 41-602's

only #4 plug looked like this see pic
all the rest looked like #8 plug see pic

[tomtom72]

I'm a bit puzzled and maybe just a bit concerned....

It's just that I don't really like the look of plug #4. That looks like oil ( or too much anti-seize? ) to me, but I don't think that I know enough to make an absolute call on it.

[FULLPWR]

Originally Posted by tomtom72

I'm a bit puzzled and maybe just a bit concerned....

It's just that I don't really like the look of plug #4. That looks like oil ( or too much anti-seize? ) to me, but I don't think that I know enough to make an absolute call on it.

I failed to mention it smelled of gas not so much of oil, one side of the tip looked good but the other side seemed fouled i guess, like it was trying to fire clean. Im confused also because when i chkd the fuel pressure it didnt leak down....when you have injectors cleaned normally at a service dept. how can they clean the sec injectors ? I did run a full tank gas w-bottle of sea foam week ago.

as of this morning:
it really does seem to be running better with the new plugs as far as getting to 6000 rpms it doesnt feel boggy like before.
but.....
still trembles at idle, i can not hear a miss in the tail pipes.
every once in awhile the idle drops off enough to notice the alternator gauge drop, just for a second then it idles ok again.
when i get to a light and stop, it idles around 1500 then slowly trickles down to below 1000 rpms, this morning it did this once "it stayed at 1500 until i goosed it a lil then it went down below 1000 rpms, but only after i goosed it."

It pulls really good to 6000rpms though seems problem is only at idle, its hard for me to tell any miss or tremble when pulling thru the gears.

I have not changed the tps yet nor have i adjusted it from .50 to .54volts.

think its possible since no leak down of fuel pressure, that maybe a dirty injector, maybe primary, not so much as a sec one, because it pulls good past 3500rpms, and no ses light at all?


Luis

[tomtom72]

Okay, smells of gas? Hey Luis, you did install new coils, right? I remember something awhile back in another thread with a miss...long & short was one of our senior members with a ton of LT5 wrench time...said that our coils could have one tower fail vs both towers fail. It was very rare, but possible.

If you have one of those spark checkers, the kind that plug into the boot and on to the spark plug, try using that to look at the spark on that cylinder in real time. Then I would transfer it to the other plug in the pair from the same coil and repeat the test. Or just do it the old fashioned way, lay a spare plug out on that wire & see what's up. Sorry, I'm not more definitive. If a plug in my old LT-1 looked like that one, I'd be all over the ignition system first just to rule it out.

The next step I figure is to try to figure out if that primary injector is fubared....maybe after checking the spark intensity, clean that plug and turn off the power key and drive the car and then pull the plugs for a look see? I know, that's a heck of a way to test injectors, sorry I can't think of any other way other than pulling the injector & looking for fouling at the tip? I know that there is a test, injector balance test, in the FSM....but I'm damned if I know how to do it!


Tom

[FULLPWR]

Originally Posted by tomtom72

Okay, smells of gas? Hey Luis, you did install new coils, right? I remember something awhile back in another thread with a miss...long & short was one of our senior members with a ton of LT5 wrench time...said that our coils could have one tower fail vs both towers fail. It was very rare, but possible.

If you have one of those spark checkers, the kind that plug into the boot and on to the spark plug, try using that to look at the spark on that cylinder in real time. Then I would transfer it to the other plug in the pair from the same coil and repeat the test. Or just do it the old fashioned way, lay a spare plug out on that wire & see what's up. Sorry, I'm not more definitive. If a plug in my old LT-1 looked like that one, I'd be all over the ignition system first just to rule it out.

The next step I figure is to try to figure out if that primary injector is fubared....maybe after checking the spark intensity, clean that plug and turn off the power key and drive the car and then pull the plugs for a look see? I know, that's a heck of a way to test injectors, sorry I can't think of any other way other than pulling the injector & looking for fouling at the tip? I know that there is a test, injector balance test, in the FSM....but I'm damned if I know how to do it!


Tom

yea i put new gm coils and ohm tested the wires too,
I saw that plug checker at auto parts, i will get it and do what you said.
then try the power key,pull plug see if it looks the same or cleaner burn.

maybe dumb question but can a code be recorded and not throw an ses light ? i am under the assumption that if no ses light, then no codes.


Luis