Help Tracking Down an Issue (1 Viewer)

[DiChristopher]

Okay so bare with me as this post may be a little lengthy but its necessary.

Purchased a 1996 KZJ71 landcruiser (180000 KM's) fitted with a 3.01KZTE. Purchased from a place in Sarasota and driven back to Tampa where it currently lives. About a week after purchase I've been dealing with a persistent issue. My RPM's upon leaving highway or cruising speeds drop drastically (almost stalling) but always seemed to correct itself. There has been no hesitations upon open throttle.

Eventually it came to the point of stalling at traffic lights. Trying to start the truck back up only resulted in it firing up and instantly dying. It would take about a minute to start back up and run fine.

I changed the fuel filter and oil, changed the fluids in the drivetrain and she ran great for about a week. Fast forward and the issue returned. Now, it left me stranded on the highway. I remember feeling a "hiccup" upon driving and it would stall out completely shortly after. I had the truck towed to the dealer where they diagnosed a fauly Fuel Pump. I found a "remanufactured" pump online and it was installed. Driving it off of the dealer lot, the stuttering and low rpm issue returned. I cleaned the injectors and it ran great, but eventually left me stranded...again!!!!

The truck is currently not starting. Fuel is making it to the pump, but not to the injectors. I hooked up power to both solenoids and the truck eventually started but in a runaway fashion. I suspect it was the ECU so I have an ecu on the way.

In the meantime....are there any other suggestions you all could give me while I'm waiting? I'm at a lost and honestly regretting the purchase of this landcruiser as it's left me stranded twice.

TIA!!

 

[jmylie]

Fuel line leak? Maybe air being sucked into the line or vapor lock?

Sediment in the fuel tank is another guess.

I hope you find it.

 

[Rigster]

I think you may be on the right track with the ECU. These PRADO's are a little notorious for having older capacitors in the ECU start leaking on them and causing some pretty frustrating issues to track down. If you are getting another used ECU it would not hurt to open it up to double check the condition of the capacitors. Open your existing one for comparison and/or to check.

There have been a mud member or two that has successfully replaced a bad capacitor on the computer board provided the capacitor guts have not damaged it too badly.

Good luck on this, and with some persistence I think you can get this resolved and hopefully remove any post-purchase regrets and get you on the road with the confidence most land cruisers provide to their owners.

 

[DiChristopher]

I think you may be on the right track with the ECU. These PRADO's are a little notorious for having older capacitors in the ECU start leaking on them and causing some pretty frustrating issues to track down. If you are getting another used ECU it would not hurt to open it up to double check the condition of the capacitors. Open your existing one for comparison and/or to check.

There have been a mud member or two that has successfully replaced a bad capacitor on the computer board provided the capacitor guts have not damaged it too badly.

Good luck on this, and with some persistence I think you can get this resolved and hopefully remove any post-purchase regrets and get you on the road with the confidence most land cruisers provide to their owners.

Thank you for the response.

I forgot to leave out i did check the original ecu. There was leakage from the capacitors. I brought it to an individual who cleans them up but he had no way of testing it. It did not resolve the issue but I'm hoping a new ECU will be a better option.

 

[Rigster]

Thank you for the response.

I forgot to leave out i did check the original ecu. There was leakage from the capacitors. I brought it to an individual who cleans them up but he had no way of testing it. It did not resolve the issue but I'm hoping a new ECU will be a better option.

No worries, that's exactly what MUD is for! When you say the individual "cleaned it up", does that mean he replaced the capacitors? If he did, then it is possible the original computer board is compromised.

Hopefully the new ECU is clean and fixes this right up!

 

[DiChristopher]

No worries, that's exactly what MUD is for! When you say the individual "cleaned it up", does that mean he replaced the capacitors? If he did, then it is possible the original computer board is compromised.

Hopefully the new ECU is clean and fixes this right up!

I'm quite honestly not sure. Better off purchasing a new one.
My thought process is the pump must not be receiving the proper power or control. I'm getting fuel up to the fuel pump but not to the injectors. Again, when power was hooked up to both solenoids they were receiving fuel. I will keep everyone updated!

 

[Shyrock]

A couple of options to check for ECU repair:
https://www.relentlessmotorsportstx.com/services
https://forum.ih8mud.com/threads/cape-fear-electronics.1265622/

 

[DiChristopher]

New ECU installed today and she fired right up.
Thank you for all of your help!

 

[DiChristopher]

Ahh one more interesting item.
She's running great however it seems the throttle isn't as "crisp" at times and seems sluggish.
Additionally the idle up button takes about 15 or so seconds to engage but when it does and I deselect it, my throttle feels more crisp than usual.
Thoughts?