renix starts then dies

My 88 xj runs for a few seconds then dies if you hold the key on it will stay running I'm lost on what it could be please help

We're you recently working on it, or did it just come up out of the blue?

It's not difficult to knock an electrical or vacuum line loose while doing repairs. I know the fuel pump ballast resistor and map vacuum line have messed with me post repair at least once each.

Jump the wires on the ballast resistor (bypass the ballast resistor) and see what happens. It is not going to hurt anything in the short term and unlikely to hurt anything in the long term. If jumping the ballast resistor cures your problem then you can try and find a new one, but they are getting hard to find. My 87 came without a ballast resistor from the factory and seemed to do just fine without it.

Greets jake88xj, The Renix models are my interest. Read your problem. Had no idea, so I do what I do, lol, and over time have come to pay good attention to those who have posted a lot of help to those of us who need it, and use different methods to hunt down for a solution(s). For example, evil google can be your friend by entering search terms, i.e., no start+hold key on+starts, and even adding sometimes a + at the end if I want to remain within this site. I absolutely can not find much use to the search engine within this site.., guess I am a techno-peasant, lol, but find google to be easier.

That said, another great thing about is after you post your question, look at the bottom of the page of the forth coming answers to you where there is a "Similar Thread" zone. Notice that that when you place your mouse/cursor over each of the 5 items down there you should see a little box that comes up on your screen that will show some further typed information as per the issue. Notice that the second one: '1989 renix starts but dies' is RENIX, i.e., those few years of production run that has many unusual problems, and difficulties to diagnose due to limited blah, blah. Anyway, in that discussion the solution was found to be a bad relay.., similar, perhaps the exact problem you have.

My thought is that perhaps the relay in yours is bad.., but too.., perhaps the contacts of the relay have corrosion under the board it plugs into. The quick fix could be as simple to find out by switching around similar relays. Also simply moving a relay in, and out can also temporarily renew the connection. If switching around your relays seems to fix your problem, check the relay to see if it is really dead.., it might not be, thusly, and possibly indicating a corrosion problem requiring further inspection. Here is the quick link to the aforementioned, one of five similar threads, i.e., the second one: http://www.naxja.org/forum/showthread.php?t=1065221 Also: Remember that our Renix machines are very old, have bad grounds.., there is a great write up on that, and we need to actually restore/upgrade lots of stuff.., :repair:

8Mud said:

Jump the wires on the ballast resistor (bypass the ballast resistor) and see what happens. It is not going to hurt anything in the short term and unlikely to hurt anything in the long term. If jumping the ballast resistor cures your problem then you can try and find a new one, but they are getting hard to find. My 87 came without a ballast resistor from the factory and seemed to do just fine without it.

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this.

and it didn't come from the factory till 89 or 90, the 87-88 models were retrofitted if the owners complained about pump noise in the cabin.

it's solely a NVH item, the pump will run fine with straight 12V.

Well guys sorry it took so long for me to get back. I was doing a cooling system swap before this happen but I have checked to see if I I unpluged something and did not find anything I bypassed the resistor and moved my relays around still same probablem i stared cleaning all the plugs I can see under the hood and that's where I'm at now

Almost certain you knocked something loose.

Hard to tell with out really knowing what "runs for a few seconds" means. Is it sputtering out like a fuel issue or just shutting off like an electrical issue?

Check engine block grounds near dipstick, they also got me once on just an oil change.

Try starting with while applying about an inch of accelerator pedal and see what happens.

Then do a volt test at the ballast resistor while cranking. The starter relay bypasses the ballast resistor while cranking. The voltage for the fuel pump goes through the ballast resistor when the engine is running and is typically a couple of volts lower on one end of the ballast resistor than the other, with the engine running.

Coolant is bad stuff for anything electrical, it conducts well and causes line leak and shorts, worse than water.

It dies just like if you were to turn the key off. I have upgraded my ground wires maybe I DoD not tighten them enough. I think I knocked something loose but I can't seam to find it. I will do some voltage test and check and clean more plugs this weekend. I'll keep you guys posted. Thanks for your help

Look at the ignition switch on the steering column down below the dash. You have to drop the column down by removing the braces, then it lowers.

The switch routes a lot of volts through it and does go bad. The big brown wire on my connector to the switch was melted and would cause intermittent no starts and eventually quit working.

87manche said:

this.

and it didn't come from the factory till 89 or 90, the 87-88 models were retrofitted if the owners complained about pump noise in the cabin.

it's solely a NVH item, the pump will run fine with straight 12V.

Click to expand...

Actually, only part of 87 came without the ballast resistor, and there was a TSB to add it in with it's associated wiring.

I would suggest the OP click on the link below and do the procedures in posts 1, 3, and 4.

http://www.jeepforum.com/forum/f140/cruisers-mostly-renix-tips-1304879/

My 87 was built in October 1986 and does not have one. A good thing apparently

It seems your fuel is shutting down as soon as the engine starts and the key is returned to the run position. This may or may not be the case. but from your description it seems so.

What you want to do is find out if you still have voltage to the fuel pump (circuit) when the motor transitions from start to run.

You can use a trouble light or a volt meter and measure voltage at the ballast resistor (a handy spot and as good as any other).

Or you can jump the orange and black wire from the BAL connection at your starter relay and hold it to a power source. The large lug and nut with all the red wires running to it on your starter relay is a handy spot. If the motor then continues to run after the key is returned to run position, you know your problem is someplace in the power supply circuit (engine running) for the fuel pump, either the relay, the wiring or a connector someplace.

It may be something else entirely, a partially plugged fuel filter, poor performing pump (fuel pressure issue). And/or the run position on your ignition is cutting off the power to multiple systems (ignition, fuel, motor management and/or something else necessary for it to run).

Process of elimination, first check out your fuel system, because that is what it appears to be. Then test the large yellow wire at your ignition module for power, with the key in the run position (because it is a handy spot and easy to get to). Test it with the key in the run position and then again while engine is cranking. You can use a test light, but a volt meter is better.

GregGA said:

My 87 was built in October 1986 and does not have one. A good thing apparently

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My 87 didn't have one, my 88 does. I've been all through the harnesses on my 88 and it looks to be a factory install, unless they replaced the whole harness.

Any starter relay with BAL (one more) connection (than the 87 or non ballast resistor setup) is likely a factory ballast resistor install. Or a late model starter relay in an early XJ with one unused connection.

In my FSM, as cruiser54 said, there is a bulletin to add one if the customer complains of fuel pump noise. I never have heard any such noise. Anyone ever had a fuel pump noise issue on a Renix and what did it sound like? Between my muffler and the stereo, maybe I couldn't even hear it

GregGA said:

In my FSM, as cruiser54 said, there is a bulletin to add one if the customer complains of fuel pump noise. I never have heard any such noise. Anyone ever had a fuel pump noise issue on a Renix and what did it sound like? Between my muffler and the stereo, maybe I couldn't even hear it

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Kind of a hum/hiss when stopped.

Well guys I bypassed the starter relay to the fuel pump and she ran. I ordered a new relay.. I think I figured it out thanks guys

Note from DJ
When you state “I bypassed the starter relay” are you referring to the large metal relay with the positive battery wire plus the fuse link wires?

A photo of this relay can be viewed in this post:
Post #7 by Saudade
This thread has a great picture of the starter relay, and all the fusible links coming off it. http://www.naxja.org/forum/showthread.php?t=97288

Yes that is what I'm referring to

I re wired mine t take standard relays.

because the renix relay is not available in parts stores, and I got tired of crawling under the jeep to start it with a screwdriver that weekend.

I rewired it in the campground.