Need Help!!!

[Dutchboy]

I have a 87 Gn that has never ran right. The person I bought it from was suppose to tune it but never did so Im having to do this on my own with no prior Buick knowledge. I have T-link 4. the car is a Bitch to start once running it idles at these values.


725-850 Rpm
Tps .43
02 Voltage 51 Mv-66Mv saw it as high as 150
02 Cross Counts 0#
Alt 13.4
Mixture is Lean
Spark Ret 0 Degrees
IAC 91 36%
Mat 90.0
Load 50#
Integrator 128
Blm 150



If anyone can help me with my problem it would be greatly appreciated. I do not know how to change these values but would like to learn if any of them need to be changed. The Gn will start the first time kinda easy but If I turn it off and try to crank it again it takes FOREVER TO get it running. I really just want this car to start better to its not almost draining the bat everytime I try to start it. Its kinda embarrassing. I would like to take it out more but it runs like a turd. Please help guys!!! Thank you in advance..

 

[413turbo]

i'm new also, but first it's looks like you need an o2 sensor- check rockauto dot com -i like the denso.
blm is high, should be around 128, could be because of bad o2 sensor.

 

[Dutchboy]

The 02 sensor is brand new. It was part of my throwing parts at it diagnosis. But I know just because I just bought it doesnt mean its good thank you though.

 

[413turbo]

well, what looks odd about it to me is that it shows 0 cc's. and should have a much higher and wider value for the o2 milivolts. which leads me to believe it is telling the ecm that it is leaner, so the ecm is max on the blm's at 150 just adding fuel to it- which is then making your engine pig rich, which then makes it not run right.
that's what i would bet is happening.

 

[notacarlo]

The o2 is not good. Also the IAC counts are too high. Needs to be in the 18-25 range at warm idle with TPS at .40-.46

 

[413turbo]

also, you could have a bad fuel pump relay (on passenger inner fender) that is causing it to take forever to crank. i think vortex buicks dot com has a troubleshoot page for it.

 

[TurboDave]

Might want to start your search looking for a vacuum leak, with the BLM pegged as they are, you've either got a vacuum leak or a pre turbo exhaust leak.

 

[Dutchboy]

I unplugged the 02 and at Idle it didnt change anything... The car ran absolutely the same. If I put my head near the turbo I can hear an exhaust leak. I dont know if that is from the downpipe or if it is the header. When ever I give the car gas like hold a stable rev of 2200 the BLM moves down a little. Also the fuel pupm relay is brand new but When I bought the car I brought it back to the shop that works on them and I have noticed that the son there takes parts from peoples cars. so IDK.. Ill check it.

 

[notacarlo]

Might want to start your search looking for a vacuum leak, with the BLM pegged as they are, you've either got a vacuum leak or a pre turbo exhaust leak.

+1

 

[Dutchboy]

Cool after church Im going to go to the parts store and pick up an 02 and the header and turbo gaskets if I can find them and install them today and see what happens.

 

[notacarlo]

For piece of mind.

One time I bought 3 02 sensors in one day! The fourth one did the trick.

What a PITA. I told the dude at the parts counter (because once the bag is open you can't return them) that I wasn't having any of their return policy nonsense. So I brought my wrench and changed them out in their parking lot to prove a point. I got my way.

 

[Dutchboy]

Do you prefer a certain brand?

 

[notacarlo]

No, not really. It just so happens I have had the best luck with Bosch.

 

[Dutchboy]

So I put a new o2 sensor in and it ran a little bit better. I looked at the Header/Turbo Flange and it is leaking forsure. Does the Autoparts stores sale this gasket? Do I have to but one from a vendor? Is there a way around having that gasket if it isnt easy to buy? If that is leaking why would it cause the car to run like *******? I would assume that it would just produce less boost.. What is the BLM and Integrator those bpth were pegged at 150 when I changed the o2.

 

[dennisL]

Here's what happens when there is a vacuum leak and/or ehaust leak before the O2 sensor. The O2 sensor tells the ecm if the fuel mixture is rich or lean and the ecm corrects it with less or more fuel. The vacuum or exhaust leak constantly makes the mixture lean so the ecm continues to add fuel until it hits the limit. The Integrator and BLM are numbers used by the ecm for fuel correction. They start at 128 and go up as more fuel is needed until they reach the limit of 150.

You have to get the exhaust leak fixed first. Then, as Dave said, make sure you don't have any vacuum leaks. After that, disconnect the orange wire by the battery, wait 10 sec then reconnect it. This erases the old BLM numbers and lets the ecm start fresh at 128. After the engine gets hot, check the IAC count for 18-25. If necessary perform the IAC adjustment procedure. Adjust your TPS each time you make a throttle screw change. Its a PITA but absolutely necessay and once set properly won't be needed again for a long time. By the way, closed throttle TPS of 0.43V is within spec but 0.44 or 0.45V is better.

 

[Dutchboy]

Thank you very much Dennis. I ordered a Turbo to Header Gasket on Tuesday. Hopefully it gets here by Friday. If so I will have the weekend to take the Turbo off and correct these issues. I went to take the Turbo off today and it was loose. There is black marks around the gasket area where the exhaust was leaking. When the car is running I could feel the leak there. So thank you for the advice I will post as soon as I get the Turbo off.

 

[Dutchboy]

getting discouraged

So I put the copper turbo header gasket in there. It still ran bad and reakkeed of gas really bad. I think that there is a leak still on the turbo. but very small.

Here are the #s
Iac 99 39%
LV8 55#
Tps .43-.45
02 volts 137mv-152mv
Mass Air 7-8 g/s
02xcount 0# But when held at steady rev it moves between Ill have to go look but I want to say 30-50
Integrator 128
Block learn 134
Mat 68.9
Engine speed 750-850


Im starting to hate this car. I was rolling the fenders today and found that it was full of rust

 

[dennisL]

Dutchboy - You don't say what the coolant temp was when you got those numbers. You're showing an IAC count of 91 which is normal for a cold engine but not so good for a warm one. The O2 volts and cross-counts don't mean anything either until the coolant is hot and the computer is running closed loop.

Get the coolant temp hot (~180) and check the IAC count. If still high, perform the IAC adjustment. There could be something else wrong too but at least the IAC would be set properly.

Dennis

 

[Dutchboy]

Temp @ 180-200 Two different Computers

ECM 1
IAC 84 33%
LV8 48-53
Tps .43-.45
O2Volts 129Mv
Mass Air 6 G/S
O2xCounts 0#
Integrator 128
Lock learn 150
Mat 75.5
Prom Id 2200

Two codes one 44 Lean 02 and the other 52 For CAL?

ECM 2
IAC 83 33%
LV8 49#
Tps .45
O2Volts 133Mv
Mass Air 6 G/S
O2xCounts 0#
Integrator 128
Lock learn 150
Mat 74.4
Prom Id 2200

One code. 44 for lean 02

Btw all the exhaust leaks were fixed and I cannot find a Vacuum leak

 

[bmackinnon]

It's bad lean... either you have a significant vac. leak (most likely) or maybe the fuel pressure is way too low. What is the fuel press.?? If you don't have a gage, you definitely need one....