Need help please....new with this

[bill grayt]

Have an 87 Ttype.
Mods include
GN1 heads
43lb injectors
front mount ic
218/218 flat tappet cam
62mm turbo
hotwired 340
alky
Ported stock tb and plenum
Built tranny with a 3200 stall


Tonight, I'm trying to tune it a bit better, because of a rough idle...has a small hiccup or miss.
Have a monitor 4000

Have TPS set at .44 closed 4.50 wot
FP is at 42 line off

At idle, warm in park
BLM reads 128

When I start the car IAC is at 140, but within 4 seconds drops to 000.
02 jumps all over between .08-.81, and correspondingly the red fuel rich/lean lights on the monitor jump constantly from rich to lean.

I set the monitor to record, and took it for a drive, to try and find out what's going on.

Got on it hard, and it power surged noticabley, then at about 16lbs boost it backfired fairly loud and let out a puff of black smoke.
The knock gauge went into the third yellow right before the backfire.

Obviously I drove it home and parked it....don't want to damage it.

I'm lost.
Any advise guys.
Keep in mind, I'm new to these cars, but very much want to learn.

Thanks in advance
Bill

 

[bill grayt]

also did a smoke test with one of those new low pressure smoke testers, and it turned up no vaccuum leaks

 

[jasjamz]

Is alky on? Who's kit? What setting? What chip? Do you have a fuel pressure gauge that you can make visible while driving? Post all the monitor numbers at idle please.

 

[TurboBuRick]

What chip?

What maf?

Have you tried to adjust the IAC?

 

[bill grayt]

Alky is an SMC kit, it is deffinately on....max setting.
I've used the test button, and it works, and the level in the canister does go down and there are no leaks.

Chip is a TT

I'm not sure what maf it is, but it isn't stock.....I'll find that out today.

I have tried adjusting the IAC, but maybe I'm not doing it correctly.....I have done a bunch more reading last night, and will try that once more.

I don't have a remote FP gauge, but maybe that's something I should look at next.

 

[bill grayt]

Did some tests again this morning.
I was adjusting IAC too much.

FP at 42 line off
TPSat .42 closed, 4.55 wot

At idle in park, car warm.

Reads
IAC 017
INT between 125-133
MAF 008
RPM 975
02 Jumps all over between .18 and .81 constantly
coolant temp at 170

Can't figure out why 02 is so irratic now

Thanks for the help

Bill

 

[mikestertwo]

02 Jumps all over between .18 and .81 constantly
coolant temp at 170

Can't figure out why 02 is so irratic now


Bill

If your in closed loop idle that is normal.

 

[jasjamz]

Drive it and see if the mass air flow reading on the scan tool goes to 255 or more at 11 pounds of boost. Also at that boost level, record the 02 readings.

 

[bill grayt]

If your in closed loop idle that is normal.

OK. thanks....rules out that

 

[bill grayt]

Drive it and see if the mass air flow reading on the scan tool goes to 255 or more at 11 pounds of boost. Also at that boost level, record the 02 readings.

I will do that tomorrow.
Again.
Thanks very much guys.

Bill

 

[in the elevens]

Is your car a t-top car? Leaking any water? Even if not when is the last time you looked at the pins on your ecm? And the condition of the wire connections that connect to it?

I had a similar issue one time and it was water leaking in and on top of the ecm and i would start the car and the idle would be all over the place and the iac #'s were very high as well.....

Just something else to consider...

 

[bill grayt]

Is your car a t-top car? Leaking any water? Even if not when is the last time you looked at the pins on your ecm? And the condition of the wire connections that connect to it?

I had a similar issue one time and it was water leaking in and on top of the ecm and i would start the car and the idle would be all over the place and the iac #'s were very high as well.....

Just something else to consider...

I'll check, it does have a small leak on the rear section of the passenger side window, but it never gets driven in rain, and I clean the drip off the inside of the window right after I wash it every time.

I'll let ya know

 

[rmar]

Have you been introduced to these fine sites?????
They are also full of good info.



Vortex Buicks



Turbo Buick Technical Articles and Resources (Technical Archives)

 

[bill grayt]

Have you been introduced to these fine sites?????
They are also full of good info.



Vortex Buicks



Turbo Buick Technical Articles and Resources (Technical Archives)

Thanks
I spent some time on these sites today.

Everything on the car now seems to be within normal peramiters, but it's raining today so no driving it.


I did replace the O2 sensor as well today, just because, but it's still the same.

So according to the TT chip info the car's readings are about what their supposed to be.

What has me worried still is the miss it has at idle or even if I hold it at any steady rpm.
It has a noticible miss or hiccuup, almost like a fouled plug.
Gonna replace all the plugs and go through the wires tomorrow, after that I"m thinking the coil might be suspect.

What do you think.

Thanks
Bill

 

[bill grayt]

Had a chance to drive the car shortly today....roads were only dry for about a half hour then it started raining again.

After replacing the 02 sensor, and setting up the IAC the surge is almost gone, but I did notice the knock sensor went to the third green at 15lbs boost, and I wasn't at wot.

I tested the coil today across all three contact points and every one was just a couple points off 12 ohms.
Next will be plugs, wires, and maf.
How do you test the maf??

Alky is full and the car goes like crazy, but I'm still worried about detonation at wot.

When I have more time I'll record what the monitor says and post the values.

Thanks guys
Bill

 

[BIGPSI]

if your getting knock at wot, either turn the fuel up or the boost down. try to keep your O2 above 750 at wot

 

[turboclam]

Any oil in the throttle body?