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  #121  
Old November 22nd, 2017, 19:42
Intellect Intellect is offline
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Re: New fuel pump, new regulator, still has fuel pressure issue..

Quote:
Originally Posted by Intellect View Post
Ill go back to my laymens terms than, my apologys. I put the key in the half turn position, half turned clockwise right before fully turning it clockwise.

Better? Lol

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I did not mean the only counter clock wise option, that only turns radio etc on. Axcuse my incorrect terminology

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  #122  
Old November 22nd, 2017, 20:00
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Ecomike Ecomike is offline
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Re: New fuel pump, new regulator, still has fuel pressure issue..



Quote:
Originally Posted by Intellect View Post
Ill go back to my laymens terms than, my apologys. I put the key in the half turn position, half turned clockwise right before fully turning it clockwise.

Better? Lol

Sent from my Moto G (5S) Plus using Tapatalk
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Quote=8Mud: "Go ahead and put up the best fence you can build, I'll bet on some Mexican with a few dollars of nails and a pile of scrap lumber."
34 MPG , '85 2WD Cherokee Pioneer with custom installed, 64 hp, 2.2 L Nissan SD22 Diesel 5 spd Manual; & 4 Renix XJs, '87 Wagoneer 4.0, 4WD, 89-Cherokee, 4WD, '87 Cherokee 2WD, & '89 Cherokee Pioneer 2WD, all 4dr. #2091
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  #123  
Old November 22nd, 2017, 20:08
Intellect Intellect is offline
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New fuel pump, new regulator, still has fuel pressure issue..

So i pulled the asd relay, looks good, nothing looks burnt up or out of ordinary. BUT it is right besides the ac relay, which had an issue. The ac relays issue was the top wire of the relay, want to say 30? That runs from the box to the battery. My jimmy rig? Ran a new wire from that prong to battery with an inline fuse.


Wonder if asd relay spot has similar issue, not sure why letting it sit for 5 minutes helps than though, im leaning ecm, pulled asd relay and tried to crank, (obviously no start) but to see how a bad asd would feel, and symptoms where different than my issue.

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  #124  
Old November 23rd, 2017, 08:27
Intellect Intellect is offline
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New fuel pump, new regulator, still has fuel pressure issue..

Its Thanksgiving, and lets just say, i let me jeep key sit half turned for 5 minutes, and it started RIGHT UP again, like i did last night, im so happy and THANKFUL i think i know the issue (ecm) lol

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  #125  
Old November 23rd, 2017, 12:00
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Ecomike Ecomike is offline
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Re: New fuel pump, new regulator, still has fuel pressure issue..

I'd be setting up the volt meter to test for low, changing voltage one location at a time just before you start those 5 minute tests to see where the low voltage drop starts at.

Start at the battery to the ignition switch, then the run to the ECM, then from the ECM to the fuel pump relay, then from the battery to the fuel pump relay, then from the FPrelay to the fuel pump.

Then do the same for the ground wires!!!!!!Current running through bad connections can heat the connections and suddenly clean then and or make better contact, on the hot wires and at the grounds.

I would make sure it is not a connection, or contact before I risk damaging a second ECU!!!!

Also have you tried simply swapping the relays???? How do you know the fuel pump relay is not going bad on the internal contacts and causing the delay??? While I doubt it is the FP relay, I would swap in a known good one anyway. I always leave the ECU for last. I have never had a bad vehicle ECU, ever. But I some in 91-95 era have been reported to have gone bad. But IIRC it was usually fuel injector firing that was fried. Same for the Renix ECU, only know of three ever reported to have a bad ECU, and it was a fried fuel inj firing transistor.

I would still suspect low voltage to the ECU!!!!! Before I suspected the ECU. There should be wiring lay outs on line here and elsewhere of the wire color on the harness going to the ECU.

Have you checked the voltage going to the fuel pump, live during the entire 5 minute delay???? Does it slowly ramp up, or just suddenly turn on???
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Quote=8Mud: "Go ahead and put up the best fence you can build, I'll bet on some Mexican with a few dollars of nails and a pile of scrap lumber."
34 MPG , '85 2WD Cherokee Pioneer with custom installed, 64 hp, 2.2 L Nissan SD22 Diesel 5 spd Manual; & 4 Renix XJs, '87 Wagoneer 4.0, 4WD, 89-Cherokee, 4WD, '87 Cherokee 2WD, & '89 Cherokee Pioneer 2WD, all 4dr. #2091
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  #126  
Old November 26th, 2017, 14:32
Intellect Intellect is offline
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Re: New fuel pump, new regulator, still has fuel pressure issue..

**UPDATE**

I wanted to wait a few days before counting my ducks. I got a used ecm and BAM so many issues where FIXED! So folks, if your check engine light/pump delay TOGETHER, I would suggest looking at your ecm.

UPDATE ON MY JEEP...

I do have to prime the system twice sometimes if it sits overnight but that is a completely unrelated issue, and for a Jeep with 246,000 miles that is an offroad/weekend toy, the ocassional two key cycles before starting is NOT a big deal to me. When i cycle the key the pump kicks right now, the check engine illuminates, and the injectors even sound like they have more "umf" to them. It felt so nice to drive 3 places and my Jeep start right up!

Now i know it is NOT suggested to get a used ecm, BUT i figured id try a used before throwing down $300+ on a remanned one. Can anyone suggest a good source for new/remanned oned with a warranty?

This used working ecm came from my buddys 200,000mile+ cherokee. 1994 2wd. Mines it a 1995 4wd. The years are interchangable. But i have no clue the miles on the ecm because my buddy said he thinks the guy he got his jeep from said that he had replaced the ecm. I believe it because it looks to have junkyard markings on it. (Can anyone figure out the mumble jumble, ill post pictures). Also his is a 1994 so the ecm should be a 94/93 but it says 1995. My 1995 ecm said 1994, but that bish was BAD. It is the best holiday gift figuring this entire threads solution at last!! BAD ECM. BAD MOFO ECM.



Now a tidbit to tickle your funny bone.

To add to my bad luck.. my fuel level gauge STOPPED WORKING. Well today i did lawnwork and moved my jeep sideways at the end of my driveway at a good slant. I go to move it after... Thing acts like it doesnt want to crank (crank start w.e the term you want to hear is), i cycle the key and hear the pump/injectors/everythings normal. I decide to jump the pump relay and it works but sounds weird. I YANK THE WIRE OUT, sounds empty is why! I get the jeep to nuetral and push a 5.5" on 35s jeep as i steer to level surface. Get her gas, and low and behold the fuel gauge didnt move! So that "quarter tank" has not been a "quarter tank" these past few days LOL. ohhhhh my luck with this Jeep. Not sure if its the ecm, or if its from removing the pump 20+ times lately, maybe i messed the floater up or it went in flipped if that makes sence.

Should i try to fix it or say f it? Votes? Lol, i probably will get bored and seenif its simple like the floater flipped or caught or bent. Floater was fine for my 600 mile excursine few weekends ago. (Trip counter never worked or i would just depend on that)


Anywho, thanks for everyones patience, it wasn A BAD ECM. BAD ECM!!!! Never been so happy to say those words.

Heck the having to prime it twice last night and this morning was probably it struggling for gas LMAO.


Ohhhhh Jeeps.....
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  #127  
Old November 26th, 2017, 14:47
Intellect Intellect is offline
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Re: New fuel pump, new regulator, still has fuel pressure issue..

Eh was tired of messing with it, but took pump out and fiddles with assembly, floater works again.
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  #128  
Old November 26th, 2017, 16:05
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Ecomike Ecomike is offline
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Re: New fuel pump, new regulator, still has fuel pressure issue..

New ECM???? "If it ain't broke, don't fix it!!" is my motto. I prefer a used working one, to one that needed remaning when it comes to electronics.

Besides jeeps have no problem finding others uses for those dollars. LOL
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Quote=8Mud: "Go ahead and put up the best fence you can build, I'll bet on some Mexican with a few dollars of nails and a pile of scrap lumber."
34 MPG , '85 2WD Cherokee Pioneer with custom installed, 64 hp, 2.2 L Nissan SD22 Diesel 5 spd Manual; & 4 Renix XJs, '87 Wagoneer 4.0, 4WD, 89-Cherokee, 4WD, '87 Cherokee 2WD, & '89 Cherokee Pioneer 2WD, all 4dr. #2091
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  #129  
Old December 1st, 2017, 16:41
Intellect Intellect is offline
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Re: New fuel pump, new regulator, still has fuel pressure issue..

CASE CLOSED. FUTURE READERS. WAS THE ECM ENTIRE TIME.

It might have had a slow bleed off issue also, that i fixed during the process.

But i let the Jeep sit Nov 25th until today Dec 1st. Sat for 6 days. Started FIRST TRY, on a cold start.

So folks, everyone overlooks the ecm, if you google everyone says ecm is probably not it. Its worth your time to check it out.

Atleast mr Jeep got a lot new upgrades during the process LOL 4 hole injectors, bosch pump, various new hoses, various new clamps.

And i know various parts are good such as tps,cps,iac, cause i either tested them or purchased a new, installed it, didnt fix it, and put oem back in.

So farewell folks! Thank you for the help! Till next time!
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  #130  
Old December 2nd, 2017, 10:37
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Ecomike Ecomike is offline
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Re: New fuel pump, new regulator, still has fuel pressure issue..

LOL, its a jeep, the case is never closed. :-)

Till next time my friend.

Congrats on the fix. FWIW, the OBD-I ECUs of all the Jeep ECU/PCMs have had the most failures reported here. But even on OBD-I Jeeps it is way less than 1% of the causes of issues. So it is always the last thing to be considered...in 11 years on Naxja I have only ween 3 reports of a bad Renix ECU, they seem to be almost bullet proof. I think 3 of them were found to have a fired Injector switching transistor, and 2 were repaired and documented here.

With all those new parts you have now, you should see a along stretch with few if any issues.
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Quote=8Mud: "Go ahead and put up the best fence you can build, I'll bet on some Mexican with a few dollars of nails and a pile of scrap lumber."
34 MPG , '85 2WD Cherokee Pioneer with custom installed, 64 hp, 2.2 L Nissan SD22 Diesel 5 spd Manual; & 4 Renix XJs, '87 Wagoneer 4.0, 4WD, 89-Cherokee, 4WD, '87 Cherokee 2WD, & '89 Cherokee Pioneer 2WD, all 4dr. #2091
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