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Trouble starting stroker.

Posted: September 20th, 2014, 7:55 pm
by Defcon92
Ok guys went to start this tonight. 92 xj 4.2l mini stroker.

1st let me say the distributor is indexed properly. I've checked it 3 times tonight! I've physically watched through the spark plug hole on cyl#1 the Intake valve open, close & watch the piston come to tdc while that's happening. The rotor is pointing at the #1 plug wire.


Anyway, is appears to not be getting fuel. Spark is their for sure, at least I think.. I zapped the heck out of myself while holding the coil plug wire. The fuel pump will prime just fine, I can hear it. It's getting fuel to the rail & injectors when I prime the pump. #1 plug was black from fuel. I installed another new napa gold brand fuel filter just to be safe.

It will start and run for about 10-15 seconds which is using the fuel from the rail. Then it will instantly die, it'll restart and repeat this same process? Would this be a bad fuel pressure regulator allowing fuel to drain back to the tank? Maybe a bad fuel pump allowing the drain back?

Re: Trouble starting stroker.

Posted: September 20th, 2014, 8:29 pm
by Defcon92
Swapped relay for the fuel pump. Did the same thing.
Jumped fuel pump using #30 & #87 runs for about 30-45 seconds allows me to rev it to 2-3000rpm then dies out shortly after. Again guessing because fuel. Sounds very good when it runs but it won't stay running.

Re: Trouble starting stroker.

Posted: September 20th, 2014, 9:05 pm
by SilverXJ
Have you checked the fuel pressure?

Also:
Defcon92 wrote: The rotor is pointing at the #1 plug wire.
http://www.angelfire.com/my/fan/dist_index.html
{quote] the rotor on the distributor should be pointing near (but not at) the mark for the no.1 plug wire terminal.[/quote]

Re: Trouble starting stroker.

Posted: September 20th, 2014, 9:06 pm
by Defcon92
New update. Through on the pressure tester on the shredder valve. Jumped the fuel pump using #30 & #87. Gauge never read above 0 psi.
Removed it, reinstalled it & used the. Key to prime it. I hear the pump humm/buzz just like it always has. But the gauge stays at zero.


Any other suggestions guys?

Re: Trouble starting stroker.

Posted: September 20th, 2014, 9:07 pm
by Defcon92
SilverXJ wrote:Have you checked the fuel pressure?

Refer to last post. Next question am I doing it right lol? My tester is autozone part# 27167 actron. Its a full, nice looking kit.

Re: Trouble starting stroker.

Posted: September 21st, 2014, 1:00 am
by Cheromaniac
You have air
You have spark

So you're missing fuel and possibly timing.
Place a rag around the schrader valve and push the valve in while an assistant turns the ignition key to the on position. If you only get a trickle of fuel rather than a fountain, your fuel pump will need replacement.
If it turns out that you DO have fuel, then either the distributor isn't correctly indexed or the timing set is a tooth off.

Re: Trouble starting stroker.

Posted: September 21st, 2014, 9:21 am
by SilverXJ
Defcon92 wrote: Gauge never read above 0 psi.
Either there is a problem with the gauge or you have no fuel pressure.

Re: Trouble starting stroker.

Posted: September 21st, 2014, 11:15 am
by Defcon92
Gonna grab a new Bosch pump today. Either that or airtex & Bosch seems better quality. Will see if that's causing this issue.


I'm getting 0 psi at the rail. But I hear the pump prime & it will start the jeep for a brief few seconds. When I manually prime it, it'll run a bit longer but it still dies. As if fuels no being supplied.

Re: Trouble starting stroker.

Posted: September 21st, 2014, 11:18 am
by Defcon92
Cheromaniac wrote:You have air
You have spark

So you're missing fuel and possibly timing.
Place a rag around the schrader valve and push the valve in while an assistant turns the ignition key to the on position. If you only get a trickle of fuel rather than a fountain, your fuel pump will need replacement.
If it turns out that you DO have fuel, then either the distributor isn't correctly indexed or the timing set is a tooth off.

The dizzy is deffeuntly in their right. 3cm from the electrical wires. Which points right at the #1 plug wire when the cap is on.
How would the timing be affecting this? I'm curious. The builder installed it all, it's the mopar 229 ab using a roll master timing set.

Re: Trouble starting stroker.

Posted: September 21st, 2014, 5:12 pm
by SilverXJ
Skip the airtex pump.

Re: Trouble starting stroker.

Posted: September 22nd, 2014, 4:57 pm
by Defcon92
Installed I have for sure pressure at the rail. I did what you said Dino and it shot a fountain over the valve cover and kept going for about 15 seconds. Need to go RE-rent that psi tester and check it out. Idk how quickly it bleeds down though. How do I test for bleeding down.

I'm still having the same issue. Pump turns on & works like normal. Much quieter though which is nice. Starts & runs for a few (10-20 seconds) then shuts off. I'm stumped at this point.

Fuel pressure regulator? Injectors? CPS sensor?

CPS is new..brand new. Injectors are new rebuilt & tested for working according to the guy on the cherokeeforum who rebuilds and test them? I'm seriously stumped?

Re: Trouble starting stroker.

Posted: September 22nd, 2014, 5:33 pm
by Defcon92
Gonna use my buddies ecu & his regulator. See if either one of those will be the issue. His jeeps running and driving so it shouldn't be an issue.


EDIT: gonna also swap out his relays for mine. Going to do each in steps to see what exactly is my issue.

Re: Trouble starting stroker.

Posted: September 22nd, 2014, 10:02 pm
by Defcon92
Relays not the issue. Swapped the a relay & starter relay with the asd & fuel pump relay. Does the same thing.


Gonna try the ecu & fuel pressure regulator next I guess.

Edit: I bridged the fuel pump resistor on the driver side fender. That seemed to make things worse. It would crank but not fire with it bridged. Hooked back into the resistor and it starts & dies again.

Come on guys bounce me some ideas. I'm going crazy after spending this much time and money on this thing. :doh:

Re: Trouble starting stroker.

Posted: September 22nd, 2014, 11:30 pm
by Defcon92
Codes pulled. Shows code 12 battery or computer recently disconnected. Code 23 incoming air temp sensor may be bad. Code 55 end of codes.


Battery or computer is obvious. It just had everything apart for a motor install lol. The iat sensor I'll check that out tomorrow but that shouldn't be causing this's run issue should it?

Btw no alarm on this jeep. Its a basic model. Manual everything even lol. I'm stumped guys.

Re: Trouble starting stroker.

Posted: September 23rd, 2014, 4:30 am
by Cheromaniac
One thing we haven't mentioned is the cam position sensor and a bad one can cause the symptoms you're describing.