Throttle makes it die

[OBEEWON]

Read through lots of problems similar but not quite the same.

1. I just swapped out my old blacktop for a new one.
2. The only changes:
Reflash from Enthalpy
Greddy Intake Manifold
Tune up parts (belts, oil plugs etc)
3. Also swapped over all my headwork and MHG

Problem:

Car starts, if I give it throttle it dies. To start it I have to open the throttle just a tiny bit then let off right away or it dies. When I rev it it sounds like its missing or in safe mode. Checked grounds, MAFS, timing is TDC, I'm running with my SAFC unplugged. I did move the ground for my Z32 MAFS to my valve cover. Fuel pressure is fine. All I can think of right now. It idles fine, just don't like the throttle.

[cotbu]

You did set you timing with a light, right? IGN Timing is 15 +-2deg BTDC. I'd also check the MAFS and TPS. Disconnect the MAFS, start the car, note any changes. Stop the car plug it back in and disconnect the tps blah blah... If those are ok and timing is set and there are no codes, try adjusting the AICV. There are things to consider like plugs fouled, boostleak, vacuum leaks etc.

[statik]

you unplugged the SAFC? did you wire the maf back to the ECU directly?

[OBEEWON]

No I didnt change any of the wiring, I checked all the injectors, coilpacks, grounds, all working. TPS unplugged shuts the car off, MAF has me stumped, I unplugged it while the car was idling but the idle is so abnormal I couldnt detect any changes.

I got it to rev somewhat, it goes up to like 2k and goes rum rum rum ( <exactly how it sounds lol not really) then drops down, this is all holding the throttle at the same position. Im checking my ecu now gonna try my old chips see what happens. I also tried moving the CAS to change timing, it will get worse but not better...

[attracted]

just for fun check the tps....i had a similiar problem on a car and thats what it ended up being

[statik]

Originally Posted by OBEEWON

No I didnt change any of the wiring, I checked all the injectors, coilpacks, grounds, all working. TPS unplugged shuts the car off, MAF has me stumped, I unplugged it while the car was idling but the idle is so abnormal I couldnt detect any changes.

I got it to rev somewhat, it goes up to like 2k and goes rum rum rum ( <exactly how it sounds lol not really) then drops down, this is all holding the throttle at the same position. Im checking my ecu now gonna try my old chips see what happens. I also tried moving the CAS to change timing, it will get worse but not better...

if you unplug the SAFC from the short harness, your ECU is no longer recieving the MAF signal, since the SAFC interrupts it (maf signal -> SAFC -> ECU), you have to reconnect the MAF to the ECU, or plug in the SAFC and zero out fuel maps and setup the MAF in/out for your setup.

[OBEEWON]

Smart man, I was assuming since the ROM tune included the MAFS I shouldnt run my old settings. Its still running and revving rough, what is the setting for the SAFC if your ROM is programmed for the Z32 already? 0 in 6 out?

[statik]

Originally Posted by OBEEWON

Smart man, I was assuming since the ROM tune included the MAFS I shouldnt run my old settings. Its still running and revving rough, what is the setting for the SAFC if your ROM is programmed for the Z32 already? 0 in 6 out?

2 in -> 2 out for Z32 maf + ecu expecting Z32 maf. Car will run with no maf signal in limp mode, can't rev it higher than 3k and wont run so great, but it will run

[OBEEWON]

OK well I was going into sensor type to check the settings while the car was idling heard a clunk, car shut off and wont start again. But the idle was getting worse slowly, and wouldnt rev freely. What the hell??

[statik]

why wouldn't you adjust the settings with the power on but the engine off? clunk+die+won't start is never good. Hope you didn't fuck something up with the timing. where did the clunk come from? what does the car sound like when cranking? if it sounds ok but won't turn over and you have spark+fuel, check compression. for now i would try fixing the SAFC settings and try starting it again as long as it sounds ok.

[OBEEWON]

Aight, got it started again, I guess the clunk was a tool in the bay or something.

Now here is a wierd issue that to me points to timing, but I swear I have the timing dead on. If I disconnect coilpacks or injectors from cylinders 1 and 4 the idle changes, 2 and 3 I dont notice a change. Exhaust is gurgling and backfiring. Again I've played with the cas and it gets worse but not better. At lest I can rev. Doesn't seem to be a vac leak as I can get my BOV to open slightly on vac after a rev.

[statik]

If there is NO change what so ever and the car sounds like its not running on all cylinders, make sure 2 and 3 are getting fuel/spark. Pull the coil out and see if it conducts on the intake mani. You can hear if the injectors are firing by placing a screw driver tip on the injector seat and placing the handle to your ear. Chances are since you didnt touch wiring all the injectors are firing. Did you do anything other than swap the rail directly to the new manifold? Last thing that can make it seem like 2 and 3 aren't firing is a lack of compression, i.e. blew the head gasket between 2 and 3. Since you did the HG im leaning towards that more than anything else. What gasket did you use? Start with a compression test.

[nightshiftgarage]

is all the vacum routing correct on the new manifold?

[johngriff]

Start with:


Pull the cas anyways.

Test for injector pulse using an led or test light on the injector clips. Do this by "key on", then spin the cas by hand and look for the led to light up.

Pull the coils, do the same with the spark plugs.

If you have signal/spark on all 4, re-punch the cas.

Test for continuity on the AFM from the plug to the ecu pin.

Test for continuity on the TPS from the clip to the ecu pin.
Set TPS to .4-.5 closed and 4.0v+ wot.

if the afc is inline, set it up 2 in 2 out.

What is the ECU tuned for, if everything has checked out up to this point, you might have an incorrect tune on the ECU.

This is the base setup. Do all this you should find an issue somewhere in here.

Oh yeah, test for compression, just so you can check it off.

Just treat it like an engineering flow sheet, and you'll end up at the problem.

[OBEEWON]

Checked timing. Its dead on TDC, re stabbed CAS. All injectors firing, all coil packs working (changed out all 4 just in case). Vac is at 20-21, AFR keeps jumping all over the place, but running rich for the most part. Some black smoke. AFC 0'd out, 2 in 2 out. Bov opens on vac after some throttle so that elims boost leak. Im stumped. Im taking out the reflash and installing old chips, doubt thats it. STUMPED!! Someone come take this car...

edit: no change with the ecu either...

[statik]

Originally Posted by OBEEWON

Checked timing. Its dead on TDC, re stabbed CAS. All injectors firing, all coil packs working (changed out all 4 just in case). Vac is at 20-21, AFR keeps jumping all over the place, but running rich for the most part. Some black smoke. AFC 0'd out, 2 in 2 out. Bov opens on vac after some throttle so that elims boost leak. Im stumped. Im taking out the reflash and installing old chips, doubt thats it. STUMPED!! Someone come take this car...

edit: no change with the ecu either...

Did you check compression? I still think its the HG.

[Chrischeezer]

check your fuel pressure... had a similar problem, bad FPR

[johngriff]

bad tune.



msg length

[OBEEWON]

Pulled codes from ECU got a 12, MAFS sensor, gonna get another Z32 tomarrow. Hopefully thats it.

Does anyone re-use thier MHG's? I've heard you can and Ive heard you can't.

[statik]

Originally Posted by OBEEWON

Pulled codes from ECU got a 12, MAFS sensor, gonna get another Z32 tomarrow. Hopefully thats it.

Does anyone re-use thier MHG's? I've heard you can and Ive heard you can't.

your MAF is most likely fine, your ECU just needs to clear itself from when you DIDN'T have the maf hooked up.

[johngriff]

MHG's? Lost.

Sounds like you have the WRONG AFM configured against the ecu, or bad wiring, I doubt its the device itself.

[OBEEWON]

metal head gasket.

It worked before for quite some time wired the way it was, I even went back to my old ecu setup to make sure. I'll update today to see if that was it. I pray it is.

[OBEEWON]

OK, You were right. I believe the maf was fine. I got a new one, same think. Found a short in the wiring. Fixed short. Still acting stupid. It actually gets progressively worse. Now I get a code 11. Holy macaroni. Camshaft Position Sensor. So I dont know if while pulling the code I didnt put the screw in the right position or what but Im getting booty loads of black smoke. So much so my Carbon Monoxide alarm goes off in my house. Anyway. Can someone give me detailed instructions for pulling codes as well as clearing them. I think I did it right but it can't hurt to double check. For now I got the batt disconnected...

For real who wants this car. No RB for me now for sure...

[cotbu]

turn diagnostic screw full clockwise for 3 sec then full counter-clockwise read codes. To clear codes I do 5 sec then back then 3 sec check again.

[OBEEWON]

To start the car, the screw should be in the same position to get the flashing light for diagnostics/original position right? because my screw can go back a little further, to the point where the light is not on.

[OBEEWON]

Why the hell am I getting a camshaft position code (11) from the ECU? sometimes I get a 55 sometimes 11, no longer do I get a 12(MAFS).

I checked timing 3 times, TDC thrice. Restabbed CAS twice, running so rich, idles crappy for a little bit then dies. I do hear a whining noise...

[johngriff]

If you are getting the CAS code on/off, it sounds like another short in the harness, to much noise over the cas wires will trip the ecu.

Test the whole harness for continuity, that should turn up all your problems.

[statik]

^^ agreed, either the CAS is malfunctioning or the wiring is faulty. considering it's on and off im leaning towards wiring.

[OBEEWON]

Im going to check the rest of the wiring. But wouldn't the car work on and off too if it was the wiring?

[johngriff]

Originally Posted by OBEEWON

Im going to check the rest of the wiring. But wouldn't the car work on and off too if it was the wiring?

too much resistance in the wiring will cause noise at the grounds and ecu and trip the codes.