cam install...now bad idle...whats wrong? Long...

Can anyone help me read a datamaster file to find out whats going on with my car?

Some info on the car:

Okay .... Im able ready to push the car off of a
cliff...

I installed a CC 236/242 on a 110lsa, CC "R" lifters,
choromemoly pushrods, pro magnum 1.6 rockers, GM
guideplates, new valve seals, EX-612 valve springs,
CSI water pump, cloyes double roller timming chain,
and a new opti with new vaccum lines. Tuning was done
by Ion Sultan.

When I first cranked it over it fired up and ran fine
except for a slightly high idle. I drive around get
the debris out of the car so that I can change the
oil, however I left the low coolant sensor clip
slightly off and the lost about 3 gallons of coolant.

I reinstall the sensor and while burping the coolant
system I accidently ran the water pump on with the
t-stat housing off....so it drenched the opti.

I drive the car home and it sputters and isn't 100% so
I attribute this to the opti getting drenched. Changed
the oil, readjusted the rockers and discovered 2 were
off the valve stem completely. Fired up the car and it
ran good but with a stumble below 3.5K rpms. I pop the
hood and saw that all 4 primaries on the passenger
side where glowing red! Next day I readjusted the
rockers and cleaned the IAC valve.... fired her up and
now she won't idle.

I swap in a new IAC valve, readjusted the rockers one
more time...and same result. So Im thinking okay...its
the damn opti..I swap out the opti today with the old
one and it runs EXACTLY the same!!!!

Someone mentioned that I should try unplugging the MAP
or MAF sensor....same result....won't idle above
950rpms like it was programed to do...sputters then
dies. If I try bring the revs past 2K it stumbles and
misfires and pops. What the hell is going on?!?!

Big thanks to Mike Leaf who drove out to my house and
helped me diagnose the car. The guy stayed till 1am!

We're still having problems with the damn car, when
Mike scanned the car it had trouble codes indicating
problems with the MAF, MAP, O2s, and it also looks
like the long term log said that its been running lean
for a while. We ran the car till it went into open
loop to get some readings.

A mechanic friend of Mike's mentioned that it might be
the injectors thats causing the headers to glow, so we
swapped out the stockers for a set of SVO
30lbers....no change. So we decided to try and adjust
the rockers, Mike went with what looked like 1/8 of a
turn after zero lash and it idled a little bit better
but still sputtered and died. This time around BOTH
headers were glowing RED.

The 2nd time Mike scanned the car after the readings
the only thing that popped up was the MAP code, the
02s looked fine but I will replace those.

Mike has the files on his laptop, does anyone know how
or who might be able to interpret them? Im still
puzzled on whats causing the glowing headers and why
it won't hold idle. The IAC is new and showed counts
of 160.

-B

Mike's Input:


> Well, I guess I can interject here a bit and tell you
> all what I saw. First off, as Binhtri said, I used
> Freescan and Datamaster for the diagnosing portion, I
> then used tunercat to "re-tune" the computer to
> hopefully help even things out. As far as the plug
> went, it looked like it had been heated up a bit too
> much, but still looked more one the healthy side than
> anything. The MAP sensor did keep popping up in the
> trouble codes after we would run the car until it
> heated up enough and went to closed loop, so Im
> thinking that this may be a big culprit. I also
> noticed when running the car with Datamaster, that it
> was showing good spark advance, but was also showing
> an almost constant 8* of retard. I couldnt figure this
> out. If anyone out there is good at reading the
> datamaster files and figuring out possible problems, I
> will gladly e-mail his file to you. (Nick? Jason?)
>
> Anyways, Binhtri was a good host even though he worked
> me like a dog (j/k)
> he did treat me to In&Out, so I cant complain.
>
> Good Luck Bin!
>
> Mike Leaf

Sounds like it it running way rich and trying to get more air (IAC counts 160).

your lobe sep might be totally fooling the 02s telling them its too lean, what are your BLM's at? see problem with huge durration & tight LSA is that so much oxygen is comming through your exhaust, & unfortunetly all the 02s read is oxygen not fuel that comes with it. I had to honestly do some major tunning & not allow for correction past 135 BLM to fix that problem, might short terms are at 145-150 range but its running like a champ at idle because my injector pulse is at 2.0 & 1.9 wihch is what it should be, not the rediculous 3.0 or so if I let the o2s correct for it at idle.

I have a datamaster file you can look at. Im still new to this stuff... so I have no idea what you just said. :(

-B

Hey man sorry to hear about your problems. That cam you have is definitely playing havoc with your computer! The solution is way more complicated to explain than the problem unfortunately and id be wasting my time writing it all out im afraid. What you need to do is contact Ion Soltan(madwolf on cz28.com) and ask him what can be done.. he will send you a new reprogrammed computer hopefully helping you out some. www.madz28.com is his webpage with his email and list of services he provides. good luck!

sure send me your datamaster file to bunker@telus.net

well just as I thought, too much fuel at idle & not enough timing, upload me your tune & i'll fix it up.

I got your email however I dont have a means to download my tune and send it to you. I maybe able to do that in the near future though.

Was this a problem with the orginal tune I got or was this the result of outside factors?

What confuses me is why did it run fine for a week.....then after I adjusted the rockers it wouldn't idle for crap?

-B

How much preload did you use initially? Maybe you bent something in the valvetrain if you had too much.

-Tony

What did you readjust the rockers to, I hope you know you need no more then ZERO lash or she won't run righ. So far the log is showing quite a bit of fuel going in, knock retard comming in & basicly not enough timing, what size injectors do you have?

I used the spin the pushrod technique where at the slightest drag I went with 1/4 turn after zero lash on brand new comp "R" lifters, it ran good for a week till I popped off the valve covers and noticed that 2 rockers were completely off the valve stem. I readjusted the rockers to 1/4 turn past zero lash again...and it never ran the same and the passenger side header started to glow.

I had a friend come over and we scanned the car and swapped out the stock injectors for SVO 30lbers, and adjusted to rockers to about 1/8 turn past zero lash. He made the corrections with Tunercat and when we fired up the car it idled longer than it did before. However now both primaries are glowing. :( And it eventually died.

-B

Ok first off you're only supposed to go MAX zero lash with Comp R's, once oil pressure builds those things don't bleed off, I had trouble with 1/8th past 0 lash she would rev past 6k & didn't idle very well, at 1/16th past zero lash I only noticed high RPM she wouldn't pull after 6500rpm, after readjust to zero lash she pulls to 7k no problems & drives fine, with Comp R lifter don't go anymore then zero lash bro, easiest & best way is do it with the car running & warmed up cuz the heads expand away from the block.

Either way, also depends on your Stud diameter, if you are using 7/16'th studs 1/16th might be too much past zero lash, with 3/8th stud 1/16th past zero lash is fine, but best is zero lash, just do it & be happy.

1/4 turn is over kill on 3/8th & especially on 7/16th studs, those valves will never close.

Would that explain the high knock, no idle, and glowing headers?

-B

Glowing headers is because like I said, at idle your injector pulse is through the roof, too much fuel & not enough timing, just adjust the rockers first bud.

Originally posted by blown383
Would that explain the high knock, no idle, and glowing headers?

-B

The glowing headers is most likely the result of your cam. With long duration and a tight LSA you have a lot of valve overlap. Back in the day this was no big deal but with these computer controled EFI motors the reversion from the valve overlap really messes with fueling. For some reason the right bank(pass side) of the motor is always the rich side with these cars.. probably something to do with the intake design and firing order. You might take a close look at your header gaskets to see if there are any leaks developing b/c that will also create the same overly rich condition you have.

Okay checked fuel pressure and at the on position it goes to 20-23psi and drops like a rock. When the car is idling (if you want to call it that) its near 40psi and without the vaccum line off it goes over 40 psi.

Bunker - Im going to try to adjust the rockers today to zero lash and see what happens. Im using 7/16ths studs.

-B

Originally posted by bunker
well just as I thought, too much fuel at idle & not enough timing, upload me your tune & i'll fix it up.

The car ran fine before on the SAME tune. The reason you see "not enough timing" is because of the knock retard which is pulling a lot of it. Very curious to know how more timing will help him when clearly, he's got a different issue.

Don't forget that you have 38# injectors and he's got stock 24#ers. The "too much fuel" issues you had with yours don't really apply here, or at least not significant enough to cause the problems he's having. Especially since the car is tuned and it ran fine on this same tune before.

okay I adjusted the rockers to zero lash and it runs ALOT better and idles longer however it still will slowly sputter and stumble and eventually die. At times it searches for the correct idle and then die.

Would bent pushrods cause a bad idle and how do I check for it?

-B

I have 3 pushrods that are slightly bent but its really hard to tell if they're bent or all 16 have a slight bow in them....or my eyes are just really ****ty....is there any sure fire way to check pushrods to see if they're straight?

-B

Acctually I got this data by looking at his logs, look at his injector duty cycle at idle, I would say thats more fuel then needed, the timing yes not enough of, can't remember what his log looked like now but I remember something like 6.2 for injector pulse width at idle!!! thats way too much if you ask me.


Originally posted by madwolf
The car ran fine before on the SAME tune. The reason you see "not enough timing" is because of the knock retard which is pulling a lot of it. Very curious to know how more timing will help him when clearly, he's got a different issue.

Don't forget that you have 38# injectors and he's got stock 24#ers. The "too much fuel" issues you had with yours don't really apply here, or at least not significant enough to cause the problems he's having. Especially since the car is tuned and it ran fine on this same tune before.

I'm glad I read this post, I also have comp R lifters and I have them set at 0 lash plus 1/8th turn. I had them at 0 lash plus 1/4 to 1/2 turn and it was running like crap. I'm going to warm the car up and set them at 0 lash this weekend and see what happens. I have never got the bugs out of my tune yet since my new motor, the car looks like a fog machine with all the black smoke coming out of the exhaust. I also think my 02's are bad, when you watch them in datamaster they will stick on a number for just a bit at random and then start to cycle normally, but they dont go way up or down they usually stay around the same range.

I really hope adjusting the lifters helps because this thing runs like crap for having 11.96:1 compression and all the money I put into it.