4AGZE troubleshooting

[cjeff]

Hi All,

Sorry if someone has this answer in the threads, I've searched for a while but hoping someone can help point me in the right direction.

Basically, I've got a Holden Nova with a AE101 GZE conversion and ECU. I bought the car only a few days ago. Drove it back from Yass to Sydney, ran fine for 2 days, I took it to the mechanic to get a service - oil, etc and a look over to get it to Wakefield this weekend. Anyway, after they finished servicing it, something has gone screwy somewhere.

Basically, it'll start but idles very rough and will stall after a few minutes, it'll rev but is massively leaning out. The engine check light is on, but when we bridge the diagnostics, the car won't read the error codes? Does anyone know why this would happen? As it's just a base Nova, it's running a Holden VL turbo Fuel pump to give the car enough fuel, but it's mounted dodgily outside the tank. Can someone confirm that a Corolla SX tank with standard fuel pump will have enough pressure/flow to fuel this thing?

Also, this arvo whilst at the mechanics while they were troubleshooting it just stopped running altogether, after pushing a few plugs on the back of the ECU it got going again - which sounds a bit like dodgy wiring, but my biggest concern is getting the error codes out of the diagnostics. Basically, the biggest problem is that it's just leaning out and the engine check light is on. Drove it fine for 2 days after I bought it, so it has been running fine, just not sure where to start, it's got the mechanics stumped atm. any help would be great...

Craig

[punkture]

haha good old 4agze issues: First, locate your ecu, you dont need to suss the cel light as its obviously on, what you have to do is locate the E2 on the ecu pinout and the corresponding check wire so like on the 3sgt T1 etc..their both pin outs on the ecu, this will bypass el dodge wiring. jump them to together. switch on on and watch the cel light.

running rough could be your AFM/map, or most likely your dizzy is it the DLI? also could be vaccuum leak, if its leaning out try taking air cleaner off and holding ur hand over the piping and see how it goes. but definately do that wire stuff i mentioned above =)

[cjeff]

Hey man thanks for the help, but just to clarify are you sure it's E2? cause on the wiring pinouts I downloaded it says that E2 is for TPS. In the 4A engine manual it says that in the diagnosis connector cluster in the engine bay to short/bridge TE1 and E1. Does that correspond to TE1 and E1 on the back of the ECU pinouts? Once again the pinouts I have downloaded for the AE101 say that TE1 is Diagnosis and E1 is intake manifold. The ECU pinout diagram also says that as well as TE1, that LG, OX, and VF are also diagnostic connectors. So which ones do I bridge from the ECU to get the CEL to show the errors?

[punkture]

Yeah i was just exampling lol, Do it from the manual so yeah, TE1 and E1, the Ox etc are also test connectors but are used to check the sensors currents etc to see if their dead, short the two you mentioned =)

[mattysshop]

FWIW i ran the stock JDM AE86 20+ year old pump with my AE92 smallport conversion..

[punkture]

FWIW i ran the stock JDM AE86 20+ year old pump with my AE92 smallport conversion..

yeah didnt think that the fuel pump would cause that issue, perhaps check the rail pressure when its running, just in case =) howd you go now? im interested to see this error code haha

[tubby]

just out of intrest what did ur mechanic do just a minor service or did he mess with stuff ? i gave mine a throttle body clean and it started acting like urs ended up a bit oh shit got stuck around the throttle plate. just a thought

[TERRA Operative]

E1 and Te1 are the pins to short.

The standard Corolla fuel pump is up to the task.

Make sure your fuel filter is not clogged.

Double check all wiring joins are soldered properly and heatshrunk (tape is not up to the taks of insulating an engine loom).

Let us know what the codes are and we'll work from there.

Oh, while you've got the pins shorted, set base timing to 10deg by rotating the CAS and checking the mark on the crank with a decent timing light (12 deg if you're feeling adventurous)

and ONLY feed it 98 octane fuel or better.

[cjeff]

Hey guys,

Thanks so much for taking the time to give me your advice, i really appreciate it.

Part of asking my mechanics to service the car (ie oils, fluids) I asked them to "go over it" with particular mention to the external fuel pump as it's the lowest part of the car - yep it's just hanging there waiting to be ripped off by whatever catches it. So they said they could tell that it's already been hit once as the bracket it was mounted on had been bent, they did mention that they had tried to push it up a bit - which may have caused a problem.

I had a read of this thread by the Witzl http://www.toymods.org.au/forums/showthread.php?t=46 on the weekend and if that's the case, then that would explain why my fuel pump was hanging so low (to be gravity fed by the tank). So moving it a bit may have upset it. So what my mechanic has done is get an EFI fuel tank for $250 (don't know whether that's a good price or not, but anyway...) and we're going to get it fitted. I sincerely hope this is the cause of it all, but if not, I'm not entirely sure this would be a waste of money as I want to get rid of the external hanging fuel pump situation.

The other thing that is a bit a of pain, is that my mechanic is a Subaru specialist (ie I used to have Subaru's) and isn't majorly experienced in this type of car, so is not completely familiar with these type of conversions. That said, he doesn't rip me off and is very good with cars and I've been using him for years, but I'm just wondering if there's anyone in Sydney who specialises in 4AGZE's who would have a much better idea of what's going on in future - and just might be able to troubleshoot stuff a bit quicker...

I took the car to my mechanic in the first place as I was trying to get to a track day on Sunday and didn't have time to look at any of it myself. So since I've missed the track day now anyway, I'll look at fixing other bits up myself (suspension upgrade, brake upgrade). The biggest problem is I don't have any working space where I live to work on a car, so I'm yet to source a place where I could leave it for weekends or a few days to upgrade stuff.

Anyway, I don't know when I'll hear back from my mech about the car, but as soon as I do, I'll let you know.

Craig

[JP]

1st things first, does the check engine light blink when the Te1 and E1 terminals in the diags block are bridged? If not, check the wiring from the ECU to the diags block as they might have butchered something in the loom. That part of the loom is usually untouched in a FWD conversion.

Check that the constant 12V is wired correctly to the ECU also, if it's not, you will lose any fault codes when the ignition is turned off.

The EFI tank is a good move, they're a much better option than an external pump with carby tank.

[punkture]

With my ta22 with 4agze conversion, i used an external surge tank, which you should have on their...should be a lifter 12v pump to the surge from the mains, then VL turbo pump to engine from surge....

As for the codes, you can do this yourself, dont waste money for a mechanic to do it.. it takes 2 minutes to do as well, do as weve all stated above, you need ZERO room to do this haha, in ur garage/driveway will do, thats where i work on mine.. this will tell you whats up and will stop you spending $$$$$$$$$$$$$$

[cjeff]

Hey punkture, with reference to room for work - i mean to swap out the brakes / suspension. I don't have a garage and my driveway is about 30 degrees sloped with no level spot - so no way I'm jacking a car up on that angle. As for the rest of it, I'll wait til the fuel tank is fitted and see what happens - it might just be fine after this. If not, depending on how bad it is, I may or may not drive it home to do the rest...

Cheers - Craig

[punkture]

ah okay, well that does cause a little problem haha, i hope its the fuel tank for your sake =)

[old_mr2]

Have you checked for a vacuum leak somewhere? Is there a boost guage fitted? What is your vacuum reading, should be sitting on 20Hg...

[86-Sh*tter]

checked the 02 sensor?