Cant get it tuned, need help

[imjoesnuffy]

All kinds of issues with my GN.

Running like crap first of all. Still have an occasional backfire/sputter after swapping injectors. Very recent plugs and wires. Just pulled them, they look fine, not fouled. Checked the coil as well resistance is between 12 and 13 between each.Did the spring cleaning things, engine cleanerchanged all vacuum lines I could find.

About to just throw my hands up and take it to a mechanic that knows what they are doing. Man this car is frustrating. Installled a Knock and Boost gauge today as well. Cant get above 6 lbs of boost before Im in the yellow, have to get out of it quick or it goes to the red.

It does leak oil, Im wondering if the leak from the intake can be causing the problem? Thinking about pulling the intake and replacing the valve springs while I am at it. What recommendation for spring? Gasket or just sealant for the intake?

FP is 42 line on/38 off
BLM 128
INT 150
IAC 38
TPS .46 at idle and engine off
02 volts are. 93 at WOT
MAF is 5 at idle

Maybe Im not understanding something, any help you can offer would be appreciated. Thanks

 

[imjoesnuffy]

?

ttt

 

[TurboBuRick]

All kinds of issues with my GN.

Running like crap first of all. Still have an occasional backfire/sputter after swapping injectors. Very recent plugs and wires. Just pulled them, they look fine, not fouled. Checked the coil as well resistance is between 12 and 13 between each.Did the spring cleaning things, engine cleanerchanged all vacuum lines I could find.

About to just throw my hands up and take it to a mechanic that knows what they are doing. Man this car is frustrating. Installled a Knock and Boost gauge today as well. Cant get above 6 lbs of boost before Im in the yellow, have to get out of it quick or it goes to the red.

It does leak oil, Im wondering if the leak from the intake can be causing the problem? Thinking about pulling the intake and replacing the valve springs while I am at it. What recommendation for spring? Gasket or just sealant for the intake?

FP is 42 line on/38 off
BLM 128
INT 150
IAC 38
TPS .46 at idle and engine off
02 volts are. 93 at WOT
MAF is 5 at idle

Maybe Im not understanding something, any help you can offer would be appreciated. Thanks

Do you ever see blm move? With int at 150 blm should be going up too.

 

[imjoesnuffy]

Blm

Well it always starts at 128. Didnt get a reading while driving but will this morning.

 

[tenright]

There is definately somethin wrong there INT drives BLM...that looks like your BLM's are locked. What chip are you using???? can't be turbo tweak..

places I found leaks affecting BLM

1) plastic vacuum block (replaced with billet vacuum block)
2) cracked passenger side and drivers side header (replaced with Postons)
3) Reversed vacuum T at the WG actuator (causing low boost, less then 10)
4) Numerous vacuum hoses routed incorrectly
5) Zip tied all vacuum connections.




T

 

[imjoesnuffy]

issues

Well I am making progress,

Did a compression test 120-130, in doing so obviously involves pulling the plugs. Found the #4 plug porcelain cracked--causing the backfire/sputter. Replaced it. Never had that happen before, first time using the NGK UR5s though. First time putting plugs in this car as well. Perhaps overtorqued it during the install, using the series of extensions and elbow joint extensions just to get to it.

Driving afterwards revealed the following: No more backfire/sputter and

MAF idle 5 WOT 255
IAC idle 16, WOT 120ish Doesn't idle below 950-1050??
INT 119
BLM 137
LV8 255 at WOT
TPS still at .46
O2 volts still at .95 at WOT

INT was trying to pull BLMs down the entire drive. On the OTC at idle it says lean. At WOT or in the gas at all it indicates rich. I did turn the FP down to 36 line on. Still can't get above 6lbs boost before I get knock. Running 93 octane with octane booster.

I did the vacuum leak check with the carb cleaner and did spray the block with no change. I did print off the vacuum routing from GNTTYPE.ORG and followed the instructions I could find when I replaced the vacuum hoses. Zip tied everyone on both ends. Got the little y vacuum thingamajig on the correct way too. Still the stock chip as far as I know, haven't done the 87 ECM conversion yet.

Is there a way to check for exhaust leaks other than pulling them? I don't hear any leaks.

Any thoughts?? Thank you for your help

 

[imjoesnuffy]

ttt

any suggestions? How do I check for exhaust leaks?

 

[TurboBuRick]

You can feel around on the headers for about a minute when you start it cold. Otherwise take a ride down a road with a median, turn off the radio and anything else that makes noise. Roll down drivers window and listen. You can hear it if your leaking. ch-ch-ch-ch-ch-ch or tik-tik-tik-tik-tik-tik. You should not hear any kind of ticks.

 

[imjoesnuffy]

tick

Well got it out and rode close to a guard rail and I am hearing a ticking under acceleration. Now how to track it down?

 

[tenright]

near a guard rail is drivers side...there is a very common spot on that header between I believe the 3 and 5 cylinders where is cracks. There should be a hundred or so posts on that one...



T

 

[Sick6]

fuel pressure should be higher with line off..haha