6776bb stutters

[87NAT]

I have finally ironed out alot of small issues with my car since the new turbo and inj install. I made some good WOT passes yesterday and the car feels like it is hitting a rev limiter at my max boost setting which is 24 psi. It is really hard to describe what it is doing. I dont think the car stops pulling but it has a small shudder. My boost gauge is fluttering at 23-24 and its almost like the turbo wants to higher but is being held back. I dont know if that makes any sense..its hard to describe on a keyboard. My fuel pressure is rising good and my A/F wideband says 11.2-11.6. It feels kinda strange. I have an RJC controller and external WG.

Could it be the converter trying to lock or unlock? It is a brand new 10" PTC 3200 L/U. For those not familiar with my posts in the last month and a half..basically everything is new(coil pack, FP, regulator, MAF, etc...the list goes on.)

I might just not be used to the big turbo and I am losing my mind from troubleshooting everyday and night. You know if you look at a problem for too long you will always find something wrong.:redface:

It could just be the characteristic of this turbo because it is a monster above 20 psi.
I basically changed the whole combination on my car. Someone tell me if Im carzy or not...

 

[John Wilde]

Are you have some back pressure issues?
What plugs do you have and what are they gapped at?
How are you valve springs holding up?

Dude, I really want your converter...

 

[Dusty Bradford]

I think the valvesprings are up to the task. I'd lean toward it blowing the spark out. Either weak plug or wire. You said you have a new coil pack.

Gap should be around .024-.028 with a plug like an ACR42TS

What rpm is this happening and will the car pull past that rpm if you hold it? If it hits an rpm wall it could be springs.

You using any kind of scan tool?

Your a/f is safe. Go over the plugs or replace them. Ohm the plug wires and see if you have a bad one. You will know if one reads much higher than the others. I have seen bad plug wires straight from the box. If all checks out, try adding a couple more #'s of boost to see if it gets worse or happens at a lower rpm. It sounds like a spark or valvetrain issue.

 

[John Wilde]

I think the valvesprings are up to the task. I'd lean toward it blowing the spark out. Either weak plug or wire. You said you have a new coil pack.

Gap should be around .024-.028 with a plug like an ACR42TS

What rpm is this happening and will the car pull past that rpm if you hold it? If it hits an rpm wall it could be springs.

You using any kind of scan tool?

Your a/f is safe. Go over the plugs or replace them. Ohm the plug wires and see if you have a bad one. You will know if one reads much higher than the others. I have seen bad plug wires straight from the box. If all checks out, try adding a couple more #'s of boost to see if it gets worse or happens at a lower rpm. It sounds like a spark or valvetrain issue.

Home, work or cell???

 

[Dusty Bradford]

cell is cool

 

[87NAT]

I am running autolite 23's which have been used during my "rich idle" condition troubleshooting which I have since fixed. They are not completely black but it looks like they are on there way out. I have always gapped at .32 for years with no issues. I guess I should change them.

My wires are they ONLY thing I havent changed in the past 2 months of troubleshooting. THey are some 10mm Taylors. They all ohm out the same. Could they be bad?

When I checked my widband log from today I had a lean spike of 17.4 A/F right when I put it to the floor then it leveled out to 10.7-11.1. ??????????

Dusty, the converter is working...I now thats not the problem..it just feels strange at the top of the boost range....but the car is pulling.

 

[Dusty Bradford]

The rich idle could have killed the plugs. If all the wires check near each other I wouldn't worry about them.

I'd do new plugs and gap them no more than .028. The closer gap won't hurt anything but will help the plug during boost. I wouldn't be worried about that lean spike with it at 10.7-11.1. If anything you could pull a little more fuel out at that boost. 11.5 is still safe at that boost level.


My car had a hesitation like that on the dyno one time. I was using old plugs. New plugs gapped down to .028 picked up another 40hp.

 

[SlickTR]

The rich idle could have killed the plugs. If all the wires check near each other I wouldn't worry about them.

I'd do new plugs and gap them no more than .028. The closer gap won't hurt anything but will help the plug during boost. I wouldn't be worried about that lean spike with it at 10.7-11.1. If anything you could pull a little more fuel out at that boost. 11.5 is still safe at that boost level.


My car had a hesitation like that on the dyno one time. I was using old plugs. New plugs gapped down to .028 picked up another 40hp.

Sounds like spark blowout to me, I'd agree on changing the plugs and bringing the gap down some

 

[87NAT]

Will change plugs today and see...cant hurt.

This was actualy the first time making good WOT passes with the new turbo. Let me pose this question: Even though I have the boost set at the same level(23-24psi) that I did with my TA-60 is the 6776bb pushing that much more air into the chambers and doing it "harder" thereby possibly causing spark blow out? Not trying to ask a stupid question...just curious.

 

[TURBO 6]

Yes, tighten the gap and try that out. I run a tight .028 on mine with high boost (25psi). Call me today, I was off last night.

 

[Nasty Wendy]

Yes, tighten the gap and try that out. I run a tight .028 on mine with high boost (25psi). Call me today, I was off last night.

OFF!!? WTF is that?

 

[TURBO 6]

Well, it was a stroke of luck. Went in like normal, nothing going on and they asked if anybody wanted to go. I was gone! I had 9.5 hours off.

 

[SMS]

I would still try another coil if you have access to one.My car was doing the exact same thing, but at a much lower boost. One of the coil towers was cracked, and under boost the spark found an easier path to ground than the plug gap.

Steve

 

[Turbo Steve]

I went thru same problem last combo plugs had to be regapped.cheap fix

 

[87NAT]

I checked my crank sensor tonight and found that I could not put a credit card to establish clearance of .25

I had removed the sensor a couple of months ago to clean it of gunk and oil that had accumulated on it and when I put it back I thought it was good but I never checked the clearance.:redface:

The metal on all 3 balancer rings was covered in the plastic from the sensor where it had been rubbing. I guess I am answering my own own question by saying this is a problem. Am I correct? If so would it cause my high rpm miss/stutter? What about affecting the idle?

Didnt drive it yet..will test it tomorrow...

 

[RUQWKNF]

Most definitely yes, it can and will affect idle and WOT. Crank sensor directly affects spark. Used as a reference to tell the computer where TDC is for #1 cylinder for firing purposes. If not addressed, it will come to a point where it will break either at idle or at speed and car will shut off. Been there, done that.
Get a new sensor and set it right, also making sure to rotate the motor completely around once it's set to make sure that none of the rings are bent. I had a bent ring on mine that took out my sensor while driving one day. Had to have the car towed home to figure out what happened as when the sensor breaks, no trouble code is thrown. From that expensive lesson, I learned what the sound of a crank sensor rubbing on the interupter ring sounds like. Kinda like a fast shhhhk shhhk shhhhk shhhk sound that speeds up as rpms go up.


Patrick

 

[87NAT]

Thanks Patrick....I will feel stupid if this has been the problem all this time that I have been troubleshooting. I ordered a new ac delco sensor..the one that is on there is not.
.

 

[87NAT]

Crank sensor fixed the problem..thanks for everyones help.

 

[John Wilde]

Crank sensor fixed the problem..thanks for everyones help.

Congratulations and new track times please.

 

[87NAT]

New baby coming in 3 weeks. Track reopens in 4 weeks. You do the math.

I will have to sell the regal for a divorce lawyer if I go to the track to soon after the new baby comes. But I will let you know what she does.