I know this has been Beat to death, but I'm still confused..

Mike97gt · Aug 20, 2007

hotstang_46 said:
sorry there 5 spd....thanks for the bumps, don't know why I called you randy... it's been one of those weeks man....

After I read your last post, I went back out and there is a definate pattern.... flashes fast for exactly one minute.....then flashes out a code....

1 flash
pause
6 flashes
pause
1 flash
pause
6 flahes

on and on

I have no check engine light and I'm not picking up any codes on my sniper interface when I run a check...... I've been PMing with SVT...hopefully he'll check in

The theft light flashing would not have anything to do with a PCM trouble code.

BUT if you see the check engine light flash while driving then that means a potentially cat damaging misfire is happening at that time.

R.J. · Aug 20, 2007

Am I missing something here? How could you possibly have done it wrong when you told VT you marked the chains to the sprockets at TDC and in the “safe zone”? (hotstang_46 we’ve pm’d about this) On reinstallation, as long as your marks all line up, you have to be correct!! They are basically saying you marked everything nice but when you put it back together, you put your chain mark next to your sprocket mark instead of on it?!?! Mistakes do happen but if you marked all the sprockets (twice) for TDC and safe then you had 8 marks that lined up when you were done!

hotstang_46 · Aug 20, 2007

RJ...... Before I opened up the car today I preceeded the work with a call to scott..... He told me my problem sounds like cam timing and I was probably off a tooth....

Upon opening up the car and removing the chains, double checking my marks, sprockets, etc.....I was surprised to find I had installed everything correctly and that Scotts and my intial impression of possibly being off a tooth was wrong....I did in fact have everything assembled properly.... I guess I just started doubting my work being I had experts telling me I was probably a tooth off

Called him again....he is stumped right now.... he mantains I don't need to degree, but it's not physically out of the real of possibilites... (he's never seen someone who HAD to degree.... none the less.....As we both decided, I'm doing a rough degree by grinding the keyway on the driver side head in order to shift that sprocket and bring down the compression to match the passenger side.... (if you didn't see it, read that little article in an above post I cut and pasted regarding it).. We're hoping the problems may be fixed ?!?!?! He and I will be talking again tomorrow if not

Everything you and I pm ed about is dead on and you should proceed as we talked....It is the right way...... I either have a situation that the guys have NEVER seen before @ VT with having to degree, or the problem lies elsewhere....

Again, any suggestions here guys would be more than welcome..... To those with similair mods...... are on stock injectors?

BobHyatt · Aug 20, 2007

I would probably just do it right the first time here. No guessing and grinding. Find TDC on #1 and make sure the TDC mark on the crank agrees. Yes, I have seen that fail so it is a worthwhile check. Then find the proper TDC index for the cam, and put it in that way.

If you suspect a fishy cam, you can check each set of lobes, but if one is off, you can only send it back for replacement.

Personally, it is too much trouble to take it apart, make a stab at it, put it back together, and repeat until fixed. I'd take the time necessary to confirm the cams are marked and ground properly, that your crank TDC is correct, etc.

I have seen bad cams in years gone by, but it has become much rarer in recent years. It is always possible that your heads are not identical for whatever reason, giving you unequal compression. Or deck height on one bank is off compared to the other bank. Or the valve job is not as good on one side. Etc. I personally think using compression to set the cam is not the right way to go.

hotstang_46 · Aug 20, 2007

I have in fact ordered a degree kit......

but Scott is 99% sure that the cams are not the culprit, being I've double and triple checked....especially being he's never heard of a single circumstance similair to mine with his stge 2 cams, given the fact that the chains are properly connected..... I will degree the cams but not now, the degree kit won't be here for another day, and I'm more concerned with moving down the list and checking off possible culprits..

while I'm in there and before putting her back we came to the conclusion it would not hurt to try a small adjustment to bring down that driver side compression a little, while far from an exact procedure it should help get the cams at least in time with each other......

i'm not expecting the car to run when I put her back together in an hour two...hoping she will, but doubtful...... hopefully scott and some of the other gentleman will continue to help me troubleshoot...

again, it's looking like my problem lies elsewhere.... I will degree, but only after I figure out where this gremlin is...

hotmustang331 · Aug 20, 2007

No, I didnt degree mine either. But seems strange that my car runs great just after the battery is reset. What about yours any change when battery is reset or no?
Man that almost sounds like a vacuum leak. My dads 306 had simular weird issues. Even though we didnt drive it, it just didnt run correctly. Everything pointed to bad lifters, and we replaced them with solid (along with the cam) still the same issue! Turned out the intake manifold gasket was leaking...some sort of defect or something. So make sure your plenum bolts are tight and the such, and make sure your MAF is clean.
Another possability is a clogged injector.

What you can do is try unplugging the injector and COP one cylinder at a time and driving it around the block to see if one doesnt see as much change as the others.

hotstang_46 · Aug 21, 2007

that's strange you say that hotmustang....

it's the strangest thing, it does run better right when the battery is disconnected and then reconnected thought not for very long......

Like tonight.....I just got done with the work.....Both banks are now identical as far as compression......

I started it up and it idled GREAT.....got into the car and was like dang, it's fixed... 1 block later I'm turning around heading back for home because it once again has a chugging hesitation running out of gas feeling...

thanks for the suggestions on the injectors......I'll give that a shot...

I'm going to try Scott again @ VT tomorrow to see if he has any suggestions..... If not, I'm really fresh out...... I just don't know where to go from here

RandyStinchcomb · Aug 21, 2007

its not injectors, sounds more like an O2's sensor issue to me. did the vac gauge tell you anything?

R.J. · Aug 21, 2007

Yeah did you ever get a good vac reading? Use one of the red tubes that come off of the big fitting on the plenum.

hotmustang331 · Aug 21, 2007

But wouldnt a bad 02 throw a code, if the 02 is not sending back a signal within range? Anytime an 02 goes bad in our other vehicles, a code is thrown .

I know my sisters car had 1 cylinder that wasnt hitting correctly (bad valves on this car...low compression on 2 cylnders though) and the car would "chug" at low RPMs but after about 3K-3500 it sounded totally smooth even driving you had no idea anything was wrong. Thats why I mentioned injector...if one cylinder isnt firing properly it can produce those effects. And odd thing was, on my sisters car, the plug looked great...thats because when the cylinder wouldnt fire, the gas was keeping the plug clean.
Just throwing out possible causes

hotstang_46 · Aug 21, 2007

I just read the vacuum....I did it at the Thicker fitting for a red hose on the plenum

it read @ idle

12 HG vacuum/ 30cm HG vacuum

maybe that tells you guys something either good or bad?

btw....I have no check engine light

RandyStinchcomb · Aug 21, 2007

hotstang_46 said:
I just read the vacuum....I did it at the Thicker fitting for a red hose on the plenum

it read @ idle

12 HG vacuum/ 30cm HG vacuum

maybe that tells you guys something either good or bad?

btw....I have no check engine light

did you run it long enuff, so that the engine warmed-up? was the needle ROCK steady? any flickering or odd movement of the needle?

12" at idle is not bad for a "cammed" engine

R.J. · Aug 21, 2007

I would call VT and ask what they think you should see for vac with their stage 2 cams. I just did mine stock and it is @22. Any and every movement of that vac needle is very important. i.e. shaking, sweeping, flickering, slowly lowering, moving to"0" under throttle, getting back to vac when let off the throttle, they all mean something.

RandyStinchcomb · Aug 21, 2007

R.J. said:
I would call VT and ask what they think you should see for vac with their stage 2 cams. I just did mine stock and it is @22.

16" to @20" is fine for a stock engine but a cammed engine will make much less vaccum at idle.

my Gt only makes @10" at 1100 rpms(thats idle on mine).

hotstang_46 · Aug 21, 2007

Do I understand this correctly?? the vacuum reading will be affected if I have a vacuum leak right? like from the plenum or intake manifold? and mine looks ok right, so no need to go ripping it apart and checking?

here's a video of the vacuum guage @ idle... you guys can see exactly what's hapenning...... ( my car idles between about 850-950rpm)

http://video.google.com/videoplay?docid=-1239947593054233206

See what doesn't make sense to me.....I've been doing some research ..... when I disconnect the car and reset it...that effectely puts the car in an open loop right? and then when the performance goes crappy after like 3/4 block or so...the car has probably switched to close loop? So it's getting some bad infor some where right? So is there someway to just have the car run constantly on an open loop?

wouldn't this cure my problem?

I placed a call over to Patrick @ sniper and he told me that the new found info that the car drives ok after the battery has been disconnected for a short while is something he can look into........ He's doing some research and I'm calling him back in a couple hours...

R.J. · Aug 21, 2007

An open or closed loop issue would be directly related to your o2 sensors. Have they ever been changed? Is it worth the $100 to try new ones?

hotstang_46 · Aug 21, 2007

At Chris's request (sniper)....I'm actually going to do some data logging while taking her down the block..... He wants to see what the front 02's are doing....

I've never replaced the 02's.....

hotmustang331 · Aug 21, 2007

^well that would be nice if all we have to do is replace the 02s . I would do it in a heart beat to fix my issues. Cant wait to see what it says.

And my car idles @ 15-16in..but right now its idling around 1000RPM. Odd though, when I first installed the turbos...for a few months...my idle vacuum stayed @ 17 @ 850ishRPM. Then one day I noticed it was 15in @ 850RPM. So thats weird. I have VT stg 1s BTW...didnt think stg 2 s would drop the vacuum that much

5spd GT · Aug 21, 2007

I would think the 02's would throw a code as has been stated...

I'm very curious to this solution, you are putting out a good effort at trying to cure this

It is strange how an 02 sensor would 'go bad' in between swaps...

hotstang_46 · Aug 21, 2007

As I wait till tomorrow to hear from sniper...... I'm sitting here wondering if there is a sensor i can pull to force my car into staying in an open loop?

I tried the Coolant temp sensor but that didn't do it....i'm guessing it just tried pulling it from somewhere else.... any ideas?

I know this has been Beat to death, but I'm still confused..

it doe snot

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