Turbo Still cuts out - 1980 Regal 5 speed

[buickman1980]

I recently purchased a 1977 Triumph Tr7 with a 1980 Buick Regal
Turbo V6 - T5 5 speed in it. I've had a problem with it since day one. In 1st gear, if I rev it up and dump the clutch, it boosts to 7 and cuts out like a governor is killing the engine - if I back the pedal off to say 1/2 way, it boost fine to 7 and maintains till I put
it to the floor again - then it cuts out again till I let off again.
The motor does not die - it just runs and does not continue to
accelerate. It also poofs a black smoke haze out while it's cutting
out. I put new platinum plugs in it, new wire, cap, rotor, most of
the vacuum hoses, took of wastegate actuator and cleaned it,
I also cleaned the PEVR, replaced air filter, rebuilt carb and used
new float. It runs and idles fine, but at full boost it continues to
poop out. It has a black box on the fender with wires running
all over the place, and it has a really old looking relay right beside
the box on the fender - The box says ESC.....
Can anyone help me or tell me where to start ?
I bought and 80 Regal dealer shop manual, but I would like someplace to start from.
From some of the postings I've looked at, some people say it
could be the plugs, could be wastegate accuator, could be coil....
What would one of you gurus out there do first ?
I would really appreciate any help .....

Thanks, Ryan
PS- could someone tell me what the horsepower of this engine is,
and if boosting at 7 is normal, or should it be going higher ?
I also run at 18 on the vacuum side at a 900 rpm idle.
I can also send pictures to you if you email me....

 

[REDS HOT AIR]

you should hook up a scan tool for one and see if its the knock sescor retarding the heck out of the timing

gm hei ignitions are know to burn thru the rotor so replace it with a good one dont buy a cheap rotor ...standard brand is pretty good

if the plugs are old then id replace them with some fresh ones and set gap around .035

that should get you started im sure more will jump in once they get out the bed...

 

[buickman1980]

Thanks Reds......

Thanks Reds.
Do you know of anyone in Denver, CO who is the the club who may have a scan tool ?
My wires are new and BorgWarner good quality - the rotor I
believe was a Standard brand - the cap I know was Standard.
I'm also going to go back to good old AC Delco normal plugs
and use your gap specs.....

Any other things I should check ?
Does it sound like it could be a wastegate actuator at all ?

Thanks in advance.......

 

[b4black]

Scan tools read the ECM, which you don't have. To see if it's reading too much knock, try unhooking the knock sensor (at the sensor) and see if it gets better. The ESC won't retard the timing without a knock sensor

You can also try unhooking the ESC controller. If it's bad, it will retard all the time. Try checking Pete's Buick Page on how to bypass the ESC: http://petesbuick.topcities.com/


One way to rule out the Wastegate actuator is to take it out of the equation. I sometimes use a turnbuckle to hold the WG closed (leave the actuator in place). Just be very careful not to overboost. It is set at ~9psi stock, so it likely isn't opening now and is not your problem. If you now goes above 7 psi, then you've found the problem.


I would go back to the regular AC's at the gap Red recommended (or maybe 0.040). Platinum plugs are for long life, not better performance. (Kinda like high-mileage tires).

 

[buickman1980]

Thanks B4Black

I'm gonna switch the plugs for sure later today -
Then I'll try unhooking the knock sensor -
Any idea what the relay is cooming off the ESC ?
If I unhook the knock sensor and it's better, should
I replace it ? Should the issue go away ?

I'll do some poking around and see If I can post
some post-test issues. I'll be back.

Thanks a ton !

Ryan
By the way, and idea on how many horses this
engine had originally ??

 

[b4black]

Re: Thanks B4Black

Originally posted by buickman1980
Any idea what the relay is coming off the ESC ?

It disables the ESC while cranking so it won't interfer with starting. It might be bad. Here's a ESC wiring diagram:
http://home.flash.net/~rjgeorge/images/wire78esc.jpg

If I unhook the knock sensor and it's better, should
I replace it ? Should the issue go away ?

A sensor could become more sensitive over time, so replacing could help. Or it might be that there is a severe detoantion problem or false knock. (take this one step at a time)

By the way, and idea on how many horses this
engine had originally ??

HP/torque figures can be found here:
http://www.flash.net/~rjgeorge/evolution.htm

 

[REDS HOT AIR]

oops on the ecm now i see its an 80 ecm's started in gm's in 81

 

[buickman1980]

Thanks Reds / B4Black

I appreciate all the help - I'm thinking of sneaking out of work and trying to work on it quick..... I'm dying to figure it out.
It's kinda like driving the go-carts at an amusement park,
You know they could be way way faster, but the gov'ner
keeps it from doing the full deal ! I feel like someone is
punishing me with this problem !!!
Thanks again for all the advise.....

Ryan

 

[b4black]

I tried a little drag racing again this weekend, and found out a couple of things about my car. First, which is related to your problem, is that it would stumble about half track, regained, stumble, etc. My first thought was not enough gas in the tank, but that wasn't it. Just like your car, it still idles and pulls to fine to point, then gives up.


The other thing is that my actuator is blown. With the Thermac Air Cleaner in place and the exhaust on, the boost limits itself to about 9, sometimes 10. With the restrictions removed (K&N and open downpipe) I saw 12 psi (and much maybe higher).


So here's my thoughts. Bad fuel pump, which can keep up only till a certain point? Bad Carb, maybe it's sucking the bowls dry? Or maybe the actuator can hold pressure until it's expanded and then releases all boost pressure? I not so sure about this one, but I'm starting there since the actuator's blown anyway. (Try checking your's with air pressure all the way up to 12-15 psi.)

But if you see black smoke, that's points away from fuel starvation. Check and see if the cutting out is correlated to secondaries opening up. Maybe they are way too rich.

 

[Ttype83]

B4Black & buickman1980 when you guys figure it out let me know. This is a problem that I have as well, Anything over 10 psi boost and it starts to break up (stumble) & backfire thru the carb. If I try to hold the boost at 10 psi (let off some gas pedal) when it shifts boost jumps up to 12-14psi and sparkknock.
I do have a vac leak that I can not find under light load,normal take off vac hits 0 or starts to boost 2 or 3 psi. If I put the shifter in low and manualy shift vac holds better.
Weak valve springs, blown HG, worn out timing chain, leaking EGR and/or vac lines are all systoms of this,, I just can not seem to narow it down.

 

[turbojolie]

i don't know how bad it affects accelration, but you shouldn't use platinum plugs in a turbocharged engine because the pressure errodes the platinum rendering the plug as junk.