JeepForum.com

JeepForum.com (http://www.jeepforum.com/forum/)
-   YJ Wrangler Technical Forum (http://www.jeepforum.com/forum/f12/)
-   -   Fuel Pressure issues (http://www.jeepforum.com/forum/f12/fuel-pressure-issues-1261011/)

duster70440 09-04-2011 01:13 PM

Fuel Pressure issues
 
I have a 1989 YJ with a 2.5L engine. I've been having problems with the jeep not wanting to start or having to cycle the key to get the engine to start. I replaced the ECU (computer) and both relays in the engine bay then I purchases a GP Sorensen throttle body regulator rebuild kit from Autozone. After installing the new regulator diaphram and injector o-rings, I attempted to start the Jeep. It wouldn't start unless I put fuel into the throttle body directly by hand. I hooked up a fuel pressure gauge and found the fuel pump doesn't turn on every time I turn on the key. When it does come on the fuel pressure goes up to about 16lbs then falls to zero instantly. If I put fuel into the throttle body it starts and runs fine and the fuel pressure stays at 16lbs. even when I free flow the pump using my snap on fuel gauge. It has a bypass button on the gauge. HELP please. Im thinking it is the fuel pume itself causing the problem. I replace the fuel pump a few years ago with one from NAPA and they have sence switched suppliers so im not sure if they will replace it, was a life time warranty pump. Anyway this is whats going on can someone help me with some suggestions. Bob

cstone94 09-04-2011 02:56 PM

I think I'm having the same problem. If I ride around and let the motor get to running temp (210) and shut it off, and try to start it after about 10 minutes, it just winds the starter. Then after about 20 minutes, it will slowly start to get ready to start and the it will start climbing from 100 RPM up until the choke kicks on. Does yours have any of the same problems as mine?

brentd711 09-04-2011 08:41 PM

My '90 2.5L TBI decided it didn't want to start when cold without a splash of fuel dumped in the throttle body. It would run all day long and restart OK if the temp didn't drop below about 190. I disconnected the wide-open throttle switch (a microswitch on the throttle cable bracket) and it has started fine ever since.

Here's my thread trying to diagnose the problem
yj-no-start-w-o-priming

nembudonna 09-05-2011 07:41 AM

Quote:

Originally Posted by brentd711 (Post 12124806)
My '90 2.5L TBI decided it didn't want to start when cold without a splash of fuel dumped in the throttle body. It would run all day long and restart OK if the temp didn't drop below about 190. I disconnected the wide-open throttle switch (a microswitch on the throttle cable bracket) and it has started fine ever since.

Here's my thread trying to diagnose the problem
yj-no-start-w-o-priming

That WTO switch seems stupid to me. I took mine off also. I know how it works but why have it?

duster70440 09-05-2011 10:49 AM

Sorry cstone, but mine doesnt do any of that. I can put gas into the throttle body and it will start then when its at normal operating temp. it will start half the time. Im going to try unpluging the WOT switch and see what happens. I will let you all know. thanks Bob

brentd711 09-05-2011 11:04 AM

I want to see the 440 Duster :)

duster70440 09-06-2011 06:25 PM

I will see about posting pics of my duster for you to see soon


The time now is 12:47 AM.

Powered by vBulletin Version 3.8.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.