so hopefully its okay for me to post

[Bob Gervais]

So there's no EEC codes when doing the KOER test? Does the CEL ever come on? Seems as though if it's running that badly, and it's due to a faulty sensor, it should kick a code.

Have you checked the compression? If there's no CEL that's where I'd start, just to rule out a junk engine/blown head gasket or something.

 

[john buck]

does the engine rev smoothly? a while back mine blew a head gasket and it felt like it had half the horsepower, but the engine still revved great...

 

[DEMONICSHO]

it revs pretty good before it gets up to temp and goes into closed loop, then it sounds horrible. i reset the computer and it would run good for about a day, then back to the same thing. the intake seems really loud. its alot harder to get up to speed. when i drive normal from a stop, and get up to 30 miles an hour the revs are at 3000. the tranny does shift fine mind you. it just seems like it has to work way to hard to perform normal driving. classic signs of a plugged cat. there has been times when i know it was running rich. and never a cel code. here is the condition ofd the car when i bought it.(both oxygen sensors were not switching, both cats were plugged. oil was disgusting. everything was changed with new parts. after that it was always detecting a rich condition on bank 1, a week later both sensors stopped working. changed them with ntks. i have never gotten a code since. but the drivability issues remained. later i took the cid sensor off and found quite a bit of oil in the synchronizer. i bought a new cid sensor and cleaned all the oil out. and reset the computer. for about 2 hours that night the car ran absolutely perfect, fast as a sho should be. and me being so happy with this had to race a newer gti, which i smoked the first time. the next light wasnt so good. it started acting up again and this dude demolished me . it took me forever to get up to 60 because of the hesatation and stumble. and its been that way ever since.:cry:

 

[93rev2sev]

Mechanically, the next steps are coolant pressure test and compression test.

Electronically the next step is: disconnect the spout connector - test drive it. It should be SLOWER. If not, you might be in limp mode and your timing is ********. I would have no idea why. but there are 2 spout connectors...make sure both are plugged in. Theres one by the cam sensor and one by the coilpack(i think).

 

[DEMONICSHO]

thanks i will check those things.

 

[artsho]

DEMONICSHO,
Here is some information taken from The SHO Registry Goody Book II....Your tachometer is run off a 22k OHM resistor. As RESISTANCE goes up your signal goes down resulting in an incorrect tach reading, that's the theory. As for a pratical application. The tach signal wire is located on the "DIS" module Pin 12 which is located at the uper right cover of the module....You need to measure resistance on that wire like you would on a sparkplug wire, but not to ground. You should measure the wire both hot and cold to see if there is a change.

 

[DEMONICSHO]

thanks art, this helps me alot. ill get on checking that.

 

[DEMONICSHO]

so everything checked out okay except one thing, fuel pressure. its 30 psi engine running at idle, but when i hit the gas it starts to go up to about 34 then drops down to 26 and thats where it stays until you let off the gas. then back to 30. keep in mind i had these drivability issues before i changed my fuel pump, filter and pressure regulator. could this possibly be the ccrm? and is that another regulator on the other fuel rail? the one without the vaccum line? i know the ccrm has two fuel pump speeds that it switches between. i wonder is it possible for the high speed relay to be bad?

 

[Off Road SHO]

That other regulator looking thing is a pulse dampener, a kind of "shock absorber" for the fuel line. Keeps the spikes and lows evened out with the pressure.

Anybody got a manual handy? Isn't the fuel pressure supposed to be held at 39 psi at idle?

Tom

 

[DEMONICSHO]

one more question, the solid black ground wire that goes to the negative battery cable. what is that the ground for?

 

[Off Road SHO]

It's for grounding some part of the engine or lighting system so is very important. Is it not hooked up?

Tom

 

[SHOZ123]

If it runs good on stock base OEM tuning but deteriorates when using the learned behavior it is definitely an air/fuel problem..

 

[DEMONICSHO]

yeah the ground is hooked up, is the ccrm a possibility in a low fuel pressure situation?

 

[DEMONICSHO]

yes? no?

 

[93rev2sev]

If so, you should have code indicating a lean condition? maybe not...I would check though.

 

[SHOZ123]

The ccrm may be a factor if there is no fuel pressure not low fuel pressure.

 

[DEMONICSHO]

no lean condition codes, no codes at all thats what i find wierd. is there anything else i should look for in the fuel system? changed pump filter and regulator already. what else would give me low fuel pressure? is the shrader valve on top of the fuel rail supposed to be capped?

 

[DEMONICSHO]

so for ***** and giggles i decided to try to pull codes 1 more time. and i finally got a code 335. egr pressure sensor. could this be causing my hesatation, lack of power etc. especially if its open and the computer thinks its shut. that would be like having one huge vaccum leak right? i also got a code 111 system clear.

 

[luigisho]

Do you happen to be around any other SHO owners? It sounds like a sensor/wiring problem but I'd love to eliminate the possibility of a faulty PCM. If you had access to another ATX SHO you could swap PCMs and CCRMs and eliminate those quickly. All the major grounds are attached and solid? Any crimped little vacuum lines like those on the back of the intake manifold? DIS module is grounded properly with the intake bolt?

 

[DEMONICSHO]

i dont know any sho owners around me, i do have a known working pcm that i have swapped out. only to get the same symptoms, ive checked and checked for vaccum hoses being off or broken etc, but cannot seem to find any. ive also cleaned every ground that i could find, trying to eliminate that as well. the only thing i can find is this egr position sensor fault during the self test. i have one on the way from rock auto, on rush delivery. hopefully that helps.