I need help!!! Sho wont run

[xxxtommyxxx16]

Hello all.

Here is my problem, I bought my SHO a few months ago and when i bought it, it needed a rely control module. (the little box above the radiator) since then i have replace spark plugs, wires fuel pump fuel filter TPS Cam shaft position sensor i have cleaned the MAF . i have taken it to 3 different mechanics and none of them can tell me whats wrong.

NOTHING HAS FIXED THIS CAR!!!

The car will not do anything but idle, When you touch the gas, it bogs or shuts off. I dont get any smoke, it doesnt run hot or smell like gas. and the only code it throws is 85.

CAN ANYONE HELP ME?????




Always appreciated!!

 

[SHObill]

does it idle indefinitely? can you light feather the gas pedal to rev it out of idle a bit while in neutral? Sounds like too much fuel is getting dumped in & she bogs & dies OR not enough fuel so she bogs & dies. Did you change out fuel filter? That new CCRM could be bad as it controls the injectors(but I think just power) &/or air temp sender in airbox is bad telling engine its -30* outside dumping in fuel. OR even MAF is bad!

 

[mrecoolgar]

TPS, throttle position sensor ?

 

[itwonder]

Have you checked the fuel pressure? Not much to go on, but maybe fuel pump or clogged fuel filter. One other thing to try that is easy. unplug the MAF and see if it runs better.

Is the idle smooth , and does it start easy.

 

[rubydist]

unfortunately, there is a long list of possible issues you could be facing. you can help narrow it down by pulling codes and letting us know what those are.

the two that popped into my head as I read your symptoms are:
1. tps (as suggested above) - if this is bad it usually sets a code
2. cam timing is wrong - I have seen cars act just like you describe if the cam timing is off a few teeth. this can occur due to sloppy mechanic who doesn't realize how critical cam timing is, or if the belt gets loose and jumps time.

you can check cam timing by pulling the upper timing cover and then turning the engine over until the 0 degree mark on the crank pulley lines up with the lower cover arrow. then look to see if the cams are turned so the marks line up with the line stamped into the rear timing cover.

 

[xxxtommyxxx16]

unfortunately, there is a long list of possible issues you could be facing. you can help narrow it down by pulling codes and letting us know what those are.

the two that popped into my head as I read your symptoms are:
1. tps (as suggested above) - if this is bad it usually sets a code
2. cam timing is wrong - I have seen cars act just like you describe if the cam timing is off a few teeth. this can occur due to sloppy mechanic who doesn't realize how critical cam timing is, or if the belt gets loose and jumps time.

you can check cam timing by pulling the upper timing cover and then turning the engine over until the 0 degree mark on the crank pulley lines up with the lower cover arrow. then look to see if the cams are turned so the marks line up with the line stamped into the rear timing cover.

Ive done the TPS and CPS, My mechanic said my timing is fine. Here's what ive found out. I put a ton of fuel injector cleaner in and it doing a little better and i also seem to have a leak in my upper intake manifold, it sounds like its coming from above the fuel rail.

Another thing, when i go over a bump, my tach comes on then off. it seems to run a little better when the tach is on, is there any connections that could come loose other than the ground on the fire wall. i will get a video of what is doing and post it on youtube if it will help you guys.

Thanks again

 

[frosho]

Another thing, when i go over a bump, my tach comes on then off. it seems to run a little better when the tach is on

This points toward a connection problem with the cam position sensor or its wiring. Try wiggling the wires while the car is idling to see if you can make the problem come and go. Look for worn spots, make sure connectors are fully seated, etc. Check the DIS connectors while you're at it.

 

[Eric VerValin]

This points toward a connection problem with the cam position sensor or its wiring. Try wiggling the wires while the car is idling to see if you can make the problem come and go. Look for worn spots, make sure connectors are fully seated, etc. Check the DIS connectors while you're at it.

x2.. Id start at that sensor, and make sure those wires going wherever they are going are ok, and not looking shorted out or anything odd. I hit a bump a month or two ago and my car did the same thing your talking about. Turned it off, then back on and it was gone. I had a TPS code, and I think a CID code but all I can think of, is I have a little short somewhere... never happened again..

Maybe double check the bolts on the DIS.... I had a SHO not start once, and then it finally did, and the only thing I did was unplug and replug in a bunch of connectors.. ?? Stranger things have happened.... also check the little mini fuses under the hood as well.

Id say your looking for something loose or crunchy... and take care of that intake leak.. that makes problems a lot worse..

 

[itwonder]

Is the ground strap from the back of the intake to the body in place? Are the two bolts that secure the intake crossover tube (DIS mounts onto it) to the intake in place? It is critical for DIS ground.

 

[SHObill]

Is the ground strap from the back of the intake to the body in place? Are the two bolts that secure the intake crossover tube (DIS mounts onto it) to the intake in place? It is critical for DIS ground.

Correct! Unless you do a proper DIS ground by running a separate wire from the 2 lower DIS screws right to a strut tower screw!