Blue Smoke

[tomtom72]

Hi Luis,

There are no dumb questions.....unless they're asked by me!

It is my understanding about SES lights or codes in general that once a DTC is set the light goes on. However a key cycle in an OBDI car will erase the code if it is not present on the next key cycle and send that former DTC to the CCM as a "H" History DTC....that is called a soft code vs a hard code like when something actually breaks. Usually our cars set soft codes if a system like the FX3 or the ABS doesn't get enough time to do a self test. I used to get soft Cam sensor codes in my car all the time until I used a different starting procedure. Okay enough about stuff that I really don't know....'puters! I stink at 'puters!

Okay new coils and the wires Ohmed out okay, but when a wire is actually on a running motor it vibrates and if the carbon core has cracks in it you would never find them if it was laying on the bench with the VOM attached to it. It's kind of like looking for the break in the vacuum cleaner cord. With what you just told me I have a bit of prejudice toward that wire @ #4 or that tower on that coil. Okay that plug could be no good right out of the box also.

The reason I suggested that checker is that it works well for the price, and remember never pull a wire with the motor running on our ignition system! That's bad for the DIS box.


Tom

[jonszr1]

try just switching holes with the plugs and see what happens . you may have a spray pattern thats gone to a stream on that one cylinder

[scottfab]

Originally Posted by FULLPWR

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


Luis

Sorry, I missed this post. And even more sorry that I did not make any others.
Are you still chasing the blue smoke thing or has you moved to unrelated issues?

[FULLPWR]

Originally Posted by scottfab

Sorry, I missed this post. And even more sorry that I did not make any others.
Are you still chasing the blue smoke thing or has you moved to unrelated issues?

after I put in the new gm coils, ac 41-602 plugs, new actuators, and fixed sec leaks, it stopped smoking, i had a bad coil so two plugs wernt firing and had a t/b ac leak, when it was smoking.
the ngk plug i pulled out and replaced with the ac'sin #4 looked half fouled and half clean.

the other day it smoke a lil after start up but went away.
so i put in a can of sea foam, and have since ran that full tank thru, was chevron, i filled up with shell just to see if it was bad gas.

currently it is trembling at idle and i have now noticed it is studdering when gettin on it, but it does not stop it from getting to 7000rpms. it wants to run like batouthell, just studders getting there.

i put that spark checker on #4 like Tom said and it is firing consistantly and bright.

i dont get it , no ses lights, no backfiring, if you read my posting i have replaced all the possible culprits, I think Brad may be on to something in regards to the injector stream s. spray, or maybe the RC's 210's are to much for it, idk...i did get 52lbs fuel pressure and no leak down so i dont think they are leaking..
when i bought them from RC i told them i had no mods i was aware of and i wanted what was best for it. Ive read in old post that based on 500rwhp 205cc is suffiecint, i hate that i made need to buy a new set...
and i dont know how to tell if i have a modded prom/chip, i am assuming i dont because im still getting pissed off with that 1-4 shift bs.

i didnt replace the TPS because the one on it chkd .50 and up to WOT it moved smooth up to 4.51 volts, although i have a new acdelco one standby. its hard to chk it holding the needles in the connector but i think i did it ok.

it studders in both engine modes so i couldnt isolate that it was prim or sec. inj. I did install them in 2006 and it hasnt been running on the road, just cranked up to keep the battery charged, so it may be they are clogged or just dirty.
thought i would run another can of sea foam in it or get that injector cleaner contraption that mounts to the fuel rail valve and try to at least clean the primary's that way, as far as the secondary's idk how to clean them without getting sec to come in.

any ideas?????

[USAFPILOT]

First...thanks for letting me take your Z on a drive; I always enjoy driving another Z. This car is a very nice example of a 90 ZR-1 as well, only 30K on the odo.

I did notice the stumble, it happens at about 3000 rpm under a load. I have a feeling a good tune is all it needs. I know it has bigger injectors than stock which could be causing it, and it has exhaust from a later model ZR-1 with the square tips just like my 94(maybe just the mufflers); but it also has different cats. I think it is just the combination of the few different parts. A dyno tune could probably take care of that last 1% to get it running like a dream. But it runs like hell and pulls hard to 7K. I think it felt as quick as my 94. I tell you what though...every time I get in a 90 I dig those tight fitting seats, they really hold you in.

As far as the smoke in startup goes...I think alot of ZR-1s do it...including mine, but you might have a little more.

It is great to meet another one of the Brotherhood...and so close by. We are going to have to hit up some car shows and do some BBQing etc.

If you do take it to Corey or need help installing new exhaust I am in.

I owe you a turn behind the wheel of my 94...just say when.

[tomtom72]

Hi Luis,

Okay we are making progress. The ignition is officially off the list of suspects.

I do believe that Brad, jonszr1, has hit the reason for that #4 plug condition. If that injector has a clogged tip then one could expect that the spray pattern will be affected negatively, which would also account for the 1/2 fouled look of the plug. A bad spray pattern will cause the miss as that cylinder's fuel is not vaporized properly. RC's normally have a tighter spray, more stream like. So it would be consistent that if trouble with the tip came up the spray would loose most of it's vaporization.

I do not know how effective those injector cleaners that plug into the fuel rail work. I have no hands on with that stuff. I would have thought that the seafoam would have been enough? I don't use that stuff either, so no hands on with that either. Once a month I use the chevron cleaner, big bottle, as my "hail mary" play.

The way I see this issue is that trying the cleaner thru the fuel rail is worth a shot...just not to have to pull that injector out. If it don't cure the issue then that injector has to come out. I doubt that there is another reason that fits the symptoms. That would also account for the darkish smoke, too rich a mixture due to bad spray pattern(s). If I had spare injectors, I'd send them to you so you could know for sure. Sorry I don't have any.

This is just some random thoughts from my thinking. Ever since I saw the vids of injectors during operation at FIC Injectors I have this bug up my shorts that the RC's don't have that great of a spray pattern. It's too tight for my taste. The Bosch II's(?) that Jon rebuilds & markets for our LT5's seem to me to be better at atomization. When you watch the vids, the difference is dramatic! Okay, all this is just my uneducated opinion and untrained observations. I might add that I'm not qualified to make such judgments since I know beans about designing injectors.


Tom

[scottfab]

Originally Posted by FULLPWR

i dont get it , no ses lights, no backfiring, if you read my posting i have replaced all the possible culprits, I think Brad may be on to something in regards to the injector stream s. spray, or maybe the RC's 210's are to much for it, idk..
(some deleted)
any ideas?????

I think too that the next stop has to be the injector check out but.....
don't rule out wire failure. I once saw a wire failure that checked out ok resistance wise but failed under load. (not a vett but same difference).
FWIW here is what an injecor spray pattern looks like for a slightly plugged OE injector at 9in from target. Note the 5 of the 6 streams are ok. This injector did not cause a problem (unlike other plugged ones) but I replaced them all with RCs in 99.

[tomtom72]

Okay, maybe I should shut up, but just humor me Luis...

Just take the #2 plug and #4 plug and switch holes with them, after cleaning the crud off of the #4 plug of course. This way I think we find out for sure if it the #4 hole & all the stuff that goes to it that is the issue. Or we find out that the plug that is / was in the #4 hole is no good out of the box. What do you think?

I know, I know, I should have stopped while I was not ahead!
I just can't figure another way, short of doing a plenum pull, again!, to make sure it's not just a bad plug or if the wire or coil or injector in the #4 hole needs to be examined. It's easier to switch spark plugs, than pull the plenum?


Tom

[FULLPWR]

USAFPILOT
SUPER Thank You for coming over and so quick too, I very much appreciate the compliments on the Z
Seeing your Z pull up and being able to gawk at it was the first time ever for me to be next to another Zr1 and yours is Beeeaauuutifullll .
Just hearing the sound of your LT5 freaked me out
I learned so much from you in just a few hours, its amazing.
I thank you sincerely. I need to get a plan together on the exhaust, get it done then call Corey. I will call you on the scheduling for the "Road Trip"
Im going to work on the stuff Tom, Brad Scottfab are pointing out before the exhuast & Corey's though.

Tom
Will do....like you & Brad said on the plug swap and see what gives.....
that fuel inj cleaner system is a little pricy, i think i'll wait to see these plugs, and put the money towards what may come up with the injectors.
I really appreciate all your effort trying to help me figure it out.

SCOTTFAB
as soon as i get the results of the plug swap, I may be pulling the plennum to do a wire swap like you suggest...and maybe i should consider putting all new wires in, since it looks like i may be pulling the plenum anyway to get that #4 injector.

....also you think maybe should i go ahead and get all the injectors tested, to make sure ??
i have read in the forum about flowtesting but have no idea on costs or who to go to, I'll do some forum searching tonite, or maybe send them back to RC......

I will post back with the plug results, shes too hot to pul plugs right now.

BIG Thanks to all of you for the guidance, ideas,and pointers !!!!!!!!
I sure am glad all of you are out there!!



Luis

[FULLPWR]

pulled #4 & #7 plugs
#4 same (half clean half fouled)
#7 clean

put new in #4 ran it
took it out - same as before (half clean half fouled)


put in new TPS
runs the same.....but......idles higher