EFI and P1300

Yep, well I guess I’ll be looking for a new computer. Sigh……

 

If you have an auto trans those PCMs are much easier to find but manual 4wd PCMs are hard to come by and expensive.

Use the part number on yours to find the correct one.

 

Any idea what could have fried your old one (lightning, reverse jump start, etc...)?

 

I don’t have the slightest idea what fried it. I spent so long rebuilding this thing, and then had to swap the engine last year. Plus it was sitting the woods for years after the original owner put over 300k on it. Could’ve been anything I guess.

 

Ok, so I drove it to work today. Ran totally fine. When I went to leave this evening, I put the key and the fuel pump would not run, just like the original issue. I cranked it, it would not start, then I stopped cranking it and heard the fuel pump running. So I cranked it again, and it started right up.

Is there anything that can cause both fuel issues and this code?????

Fuel pump?????


Please please please please please help me

 

Assuming you installed that ignitor.
And no change?

 

The igniter hasn’t came in yet.

I’m just trying to pinpoint things that could cause both this code and the fuel issue…

 

A firm.

anyway you can bench test the old ignitor?
U seem to have much better Multimeter skills than myself!

btw, would love to see a pix of this ignitor and where located

 

I don’t know how I would test the igniter, though I’m sure there’s a video or something I could find.

The igniter is located on the fender behind the air box and under the cruise control box.

The ground was pretty rusted when I took this photo last week, but I already took care of that and cleaned up the grounds. No difference though

 

The capacitor on that board is an electrolytic capacitor and looks like it may have leaked. They tend to do that when they start to age. You can replace it and fix the traces on the board if need be. If you have a way to test continuity across each one of those traces, that'd be a good place to check.

 

Would the computer cause the fuel pump to not get power intermittently?

I replaced the EFI but I did not check the COR relay, could this cause it?

I just feel like whatever is causing this fuel issue, if I fix it the code will go away. Just a feeling I have…

I could also have a bad fuel pump I guess, I replaced it when I built the truck a few years ago, but it has always ran continuously when I turn the key on. It doesn’t stop running, even after I know it has built up pressure.

 

Absolutely a PCM problem can cause the fuel pump to not run as the PCM controls the C/OPN (Fuel Pump) Relay.

It's not right for the pump to run any time the key is on either, it should only run during cranking and once the engine starts.

 

Funny because that fuel pump has always acted like that.

So I guess I’m back to my original conclusion that I need a new computer.

I guess I will take a look at the COR relay, because I guess if it was stuck open it could cause it to constantly run? And if it could also stick shut then that could explain it sometimes not starting or the pump running??

I feel like maybe if it was the computer causing this, it would be more consistent instead of intermittent?? Maybe?

Either way, I still will be looking for a computer, I don’t like the look of that capacitor and circuits are 1 thing that I don’t quite trust myself trying to fix..

 

I thought leaking caps in the ecu was a early 90s problem, but that cap in your pic looks to be leaking on the board....not good, as someone else mentioned that goo can damage the traces disabling certain functions of the ecu. If you cant find a replacement ecu for a reasonable price there is a guy in Texas that repairs Toyota/Lexus ecu,s . Relentless Motorsports tx (972) 779-6862 have seen this guy mentioned in other forums never heard anything negative. Also this not your issue but try to keep your case grounds clean, mounting points between ignitor case and fender, ecu case to firewall retention clip.
Another quick note, that ignitor is very common to 4cly toyotas and older lexus v8,s have two of them also on corollas and camrys, plentiful in junk yards, nice to have a spare for troubleshooting. Hope you get things resolved
R/
Andy