Cardone MAF

[tskdave]

Dave here again, with the 85 GN. Car is running pretty good, but have a quick question. The Cardone maf I bought I thought was working well. Took the car out for a spin with the t-link hooked-up, heres what i dont understand. I know the stock maf maxs out at 255. Mine is only showing 155 on the t-link dashboard screen. At wot the highest i'm seen is about 207???? Maybe this is why I can't get over 11 lbs of boost???? Other wise the car is running pretty good. any ideas???? Thanks, Dave

 

[tskdave]

o.k. just got home from work, put the stock delco maf back in.....same thing, the chart on the t-link only goes up to 150. Took it for a spin, reading went up to about 185????? I thought I was on to something, but maybe not?????? Anyone?????

 

[Jerryl]

Dave here again, with the 85 GN. Car is running pretty good, but have a quick question. .......... I know the stock maf maxs out at 255. Mine is only showing 155 on the t-link dashboard screen. At wot the highest i'm seen is about 207???? Maybe this is why I can't get over 11 lbs of boost???? Other wise the car is running pretty good. .......

Dave,
Not sure if the MAF in your case limits boost pressure. IHMO, I do not belief that the MAF would be so restrictive you could not get more than 11 PSI boost. There are other issues. A few things I would personally verify before focusing on the MAF flow.

1. How do you measure boost and where is the gauge hooked up at?
2. Re-installed and verified the plastic orifice T yet? http://www.turbobuick.com/forums/showthread.php?t=166871
3. How is the exhaust? Is the CAT plugged up?
4. What air filter do you have on the car?
5. What condition is the boost solenoid in?
6. Does the TB open all the way at WOT?

 

[tskdave]

Thanks for the reply. The VDO boost gauge is hooked up right into the intake, I just put a new "t" in vac lines(restriction towards the turbo. I have a gutted cat, no mufflers, with k+n filter. the only thing I haven't changed is the boost solenoid. I thought they either worked or the dont.....any way to test??? All good ideas.....keep em coming... Thanks Dave

 

[Jerryl]

Thanks for the reply. The VDO boost gauge is hooked up right into the intake, I just put a new "t" in vac lines(restriction towards the turbo. I have a gutted cat, no mufflers, with k+n filter. the only thing I haven't changed is the boost solenoid. I thought they either worked or the dont.....any way to test??? All good ideas.....keep em coming... Thanks Dave

Good question on the solenoid test!
Try this thread.
http://www.turbobuick.com/forums/showthread.php?t=154264&highlight=solenoid+test

Does the wastegate or exhaust leak anywhere?

 

[tskdave]

o.k. forgot I bought a new boost solenoid a couple of months ago. Just went out and put it on the car, same results. Only getting 11 lbs boost max. I have got about 3/8-1/4 inch left on the actuator threads. Should I just keep cranking it in to see what happens??? I tried straight from turbo to actuator still only 11 lbs. Cant see/find/hear any exhaust leaks. Bad actuator???? Running out of ideas....... Dave

 

[Lee Thompson]

boost

DO NOT get your boost signal from any of the lines that are attached to the wastegate solenoid. The WG solenoid is an electrical bleed valve. You can and probably are, bleeding pressure off your boost gage. Go behind the fuel pressure reg. and use the unused 1/8 in. NPT port there. Now you will be reading directly off the intake. Best of luck.

 

[tskdave]

My boost gauge is right off the intake....nothing to do with wastegate solenoid. Starting to think the actuator is bad... Dave

 

[Jerryl]

........... I tried straight from turbo to actuator still only 11 lbs. Cant see/find/hear any exhaust leaks. Bad actuator???? Running out of ideas....... Dave

Not trying to insult your intelligence but I am unclear of your description.
Let's see if I understand you correctly.
You took the hose from the turbo pressure nipple and ran it straight to the actuator?
Did you use the “T” in this experiment?

Did you disconnect the pressure hose at the actuator, plug it and then see if you got boost? Again, I am no expert, but this is what I see IMHO.
Here are a few “If – And - And - Then” statements

If:
You in fact disconnected the hose to the WG actuator and plugged the hose thereby eliminating most other boost control variables
And:
As you stated, your exhaust is open and no leaks, use an aftermarket known good VDO hooked up from the nipple behind the intake, and the adjustable WG rod has tension on it
And:
STILL only see 11 psi boost on the VDO
Then (I say Unto thee):
You may have a bad actuator (broken spring), a puck that leaks (loose), or, a damaged impeller not allowing more boost.

See if you can move the actuator in and out and if the “spring” pushes the WG rod back.

 

[Jerryl]

PS
Are you sure the hoses are connected this way?

 

[tskdave]

Sorry for the bad desciption, here's what I tried. I took a vac hose straight from the actuator to the turbo...removed the t for this experiment.....11lbs. Then I put the t back in, yes it is installed correctly. Somebody told me to remove all vac hoses(cap them all) to the actuator, and drive....real easy because the boost will go up??? should I try this???? . Also no play in the actuator.....Thanks, Dave

 

[Lee Thompson]

try this

Unhook the wastegate rod and see how much boost it will make. Next hook rod back up, but no hoses and drive --boosting up with you eye glued to the boost gage. This will tell you if your tubo is good, assuming no leaks.
Sorry about my first post--did not read your post carefully..
You wastegate soleniod is a bleed valve--I think if it is bad your boost will be higher.

 

[tskdave]

That sounds like a good easy test to do!!! I will try tomorrow when I get home. Thanks, Dave

 

[tskdave]

I tried unhooking the wastegate, and went for a spin. The car wouldn't even run right. sputtered, ses light came on, and felt like it was missing. no codes. Reset the ecm, hooked everything up stock....now the car won't run right.... Dont know what to do. any more ideas???? Dave

 

[Lee Thompson]

?

Did you unhook the WG rod or unplug the WG solenoid. Must keep WG solenoid plugged or a code will be set. Should be able to clear code and run good again after a few miles assuming something else is not going on.

 

[tskdave]

I just unhooked the wastgate, left the solenoid plugged in. I can't get the car to run right again....Dave

 

[Lee Thompson]

Bang

Get your gun out and shoot it!!!!

 

[tskdave]

I would like to shoot this car......but that would be to quick. I would like to cut+quarter this P.O.S. I quess I have to much money into this to give up now. I wish I still had my 82 GN. Sold it 10 years ago,not fast but one nice car. Mine had 63k no rust, perfect body and interior. Probably worth something now!!!! Oh well, live and learn.............Dave