Bigscotian

From what I can gather those codes are for the air intake sensor short or open and maf sensor faults. I've tested the maf sensor as per the FSM and it tested ok to my surprise. This is leading me to a wiring issue. I'm just wondering if anyone has come across this so I can find the spot that may be causing the issues a little easier. I really want to just run new wires for the circuit but at the same time, dont want to deal with the problems later again if there is a problem with chafing, water or something else that needs fixing. I've looked over the harness in general without pulling off too much tape and tubing and hav'nt seen anything obvious.

I should also say that the truck does seem to start at different times of the day, say for instance in late afternoon after its been in around 10 celsius for most of the day, but still is hesitant and dies when put under the slightest load.

Not sure if I'm just dealing with one problem or several here, but any help will be appreciated, thanks.

4Crawler

iTrader: (3)

What is the exact nature of the "no start" problem? Engine does not turn over at all, or cranks and cranks w/o starting?

Bigscotian

The engine turns over as in the starter engages and turns over freely however there is no ignition. Any ideas?

4Crawler

iTrader: (3)

You might try the fuel pump test jumper to ensure the pump is running:
- http://www.4crawler.com/4x4/CheapTri...shtml#FuelPump

Bigscotian

I jumpered Fp and B+ and I can hear the fuel pump. I dont have anything to check nor do I know how to check the fuel pressure. Any idea about the codes coming up and the AFM is good?

4Crawler

iTrader: (3)

Since the pump is running, did you try starting the engine? All that jumper does is bypass all the normal things that turn on the fuel pump and just make it run. You could crack the connection on the cold start injector and see if fuel leaks out to check for pressure. Or on my truck, I drilled and tapped the fuel injector ail and installed a fuel pressure sender to connect to a gauge on the dash.

Bigscotian

I did try starting it with the fuel pump jumpered to the same result. There is fuel getting to the fuel rail. I still dont have any way to check the pressure but its a new pump in a new tank less than 6months old. I put a new fuel filter on as well.

So far what Ive done today was to rewire a few things, I bypassed the E2, THA, Vs and Vc I believe, the sensor ground wire, intake air temp sensor wire and the two for the air flow meter. It seems like it almost wants to start but won't, just a few chugs then just keeps turning over. I have yet to solder the connections so I'm thinking that is'nt good. Going to solder up those wires proper, then clear the codes and try starting it again.

4Crawler

iTrader: (3)

One way to check pressure (sort of) is to either pinch off the return line from the pressure regulator or apply vacuum to the vacuum port on top of the FPR and listen for a sound change from the FPR. Typically sounds like a small air leak (kind of a hissing sound) and the character of that sound will change with fuel pressure (the above tests change the fuel pressure).

Bigscotian

I'll check to see if I can see any difference with that test. I also found a bad wire on a connector on the coil/igniter, the black/red stripe wire, its pretty crappy looking. The FSM shows it going to the injectors for some reason. Wondering if you going at a fuel problem and this bad wire to the injectors may have something in common.

crackerhigher

I know this is an old post but was there any update on what the cause was? I have the same exact issue with the same exact code 24 and 31

Bigscotian

I ended up running new wires for the circuits affected... just look up in the factory manual for the codes, I forget what circuits are actually affected, and check those wires from the AFM to the ECU.

On a side note this truck has'nt had much work put into in the past little while and its still not starting. Will turn over but no ignition. I've narrowed it down to the coil pack however am having an impossible time finding a replacement. For some reason every junker one I find is a different setup so the connectors from the wiring harness plugging in are different. I'm pretty confident its just not getting enough spark now, hoping I can find the right coil pack soon.

crackerhigher

Did running new wires from the AFM to the ECM fix your the code 24 & 31 you were getting for the affected circuits?

RBX

I know this is old, but inquiring minds ant to know....any results?

crackerhigher

I know when I had code 24 & 31 on my 91 toyota pickup I ran new wires from the AFM to the ECU and this fixed that issue I had. There apparently was a short somewhere in the harness and it was just easier to run new wires instead of tracking down the short in the wire. Hope this helps.

RBX

Thanks cracker