Jeep Wrangler Forum

Jeep Wrangler Forum (http://www.wranglerforum.com/)
-   YJ Tech Forum (http://www.wranglerforum.com/f218/)
-   -   noob help (http://www.wranglerforum.com/f218/noob-help-214885.html)

jstiley1 01-26-2013 09:39 AM

noob help
 
I/we have an 89 Wrangler with the 2.5l. It was inherited by my wife with her divorce..It wasnt running when we got it so i dont know if he sabotaged it..I work on cars and always have but this jeep has stumped me...My first go at it was after we got it 10 yrs ago.I replaced many parts which ill list at the end and still no go...it sat for many years due to frustration...But now im ready to have another go at it...Im still throwing money at it and still no luck..It will crank and crank the every so often back fire out of the intake..Its getting fuel its getting spark..Its driving me crazy..New parts list: Cap, rotor, distributor, plugs, wires, coil, ignition module behind coil, crank position sensor,timing chain

help me and my wallet

Nubby55 01-26-2013 10:03 AM

check firing order?

jstiley1 01-26-2013 10:07 AM

Firing order is good..I even tried to advance all one and retard all by 1 ..

rykemc 01-26-2013 10:28 AM

What do your plugs look like? Are the fouling out?

jstiley1 01-26-2013 10:32 AM

They are brand new but are getting black from cranking

bajonesy77 01-26-2013 10:56 AM

Does it have fresh gas in it ?

jstiley1 01-26-2013 11:02 AM

No..that was my next goal drain tank and try that.
seems like it would atleast start and run bad with bad gas though...right now its cranking and bout every 10 seconds it will backfire thru intake

Airboatingobx 01-26-2013 01:29 PM

Drop the tank and drain the gas then drain the carb, then put in a can of sea foam and around 5 gallons of gas and crank it up should run like crap till it gets the varnish out. Might want to go ahead and rebuild the carb or up grade and replace it with a motorcraft carb.

88Sahara 01-26-2013 02:43 PM

Even if the plugs wires are all sorted out, the timing could be way off. Backfiring through the intake can happen if it is way off.

88Sahara 01-26-2013 02:51 PM

Just reread that you replaced the CPS and timing chain. Backfiring is still usually some sort of relation to timing though. Timing set off by one tooth?

jstiley1 01-26-2013 03:44 PM

ok drained tank, now fresh gas...still same issue...chug chug chug, poof..if i hold down gas it will shoot a flame...im done for the day....i guess ill pull timing chain tomorrow...maybe i didnt install it right the 1st time...any advice for the next go around? thanks again for all the advice

rykemc 01-26-2013 04:09 PM

Before pulling timing chain you can check the timing by pulling valve cover and looking at #1 cylinder valves. If you turn your ballancer where the timing mark is at TDC. The timing mark on ballancer should be even with the 0 degree mark on your timing cover. Make sure piston is at TDC on #1 cylinder and check your intake and exhaust valve on that cylinder. Both valves should be closed. If all that checks out, then pull dist cap and see where your rotor is pointing.

I should also point out that on the exhaust stroke the timing mark will be pointing to 0 dregrees but the exhaust valve will be open so make sure you check the valves on the compression stroke

88Sahara 01-26-2013 04:19 PM

Only other thing I can think of is that the distributor might be stuck at full advance. That would produce enough timing difference to do the same thing as the chain being off a tooth or two.

Lean condition can cause it too. Have you checked the injectors themselves? Could be getting to the injectors but if they are plugged, would cause it to be lean enough to backfire.

Let us know what you find out. If I think of anything else, I'll post.

brentd711 01-26-2013 06:22 PM

I'm guessing your distributor is set 180 degrees off. Been there, done that.

Mr.Mud 01-26-2013 08:20 PM

Never hurts to pull the plug out of your catilitic converter to make sure its not clogged or the dude stuck a potato in the tail pipe

93wrangler-yj 01-27-2013 01:20 AM

Check fuel filter?

jstiley1 02-01-2013 09:38 AM

Sorry its taken me a while to get back in here I'm a weekend warrior due to full time job and 4 kids...
On ditstro. I have put it in as the chilton said and rotor is at 6 o'clock at tdc...so I assume I'm ok there...I am going to do timing chain again just in case...something has to ?
be off due to the backfire...any one have a link for replacing chain..I have a chilton but.......

Fishnic 02-01-2013 11:46 AM

Quote:

Originally Posted by brentd711 (Post 3282317)
I'm guessing your distributor is set 180 degrees off. Been there, done that.


My 88 PO pulled the rotor and put it back in prob 45 degrees off, i could not get it to fire at all, some small backfires.

I had to rotate the engine until i had Cylinder 1 at TDC and checked the distributor to see if it was in the correct firing position.

I kept lifting the rotor out and advancing it until i got her into the correct position and it has been running great since.

I am not sure it is the same for an 89, but it absolutely didnt make any sense at all to me while i was troubleshooting it.

brentd711 02-01-2013 04:02 PM

Quote:

Originally Posted by jstiley1 (Post 3307536)
I have put it in as the chilton said and rotor is at 6 o'clock at tdc...so I assume I'm ok there...I am going to do timing chain again just in case...something has to ?
be off due to the backfire...

The rotor has to be pointing at the #1 plug position with #1 piston at TDC on the compression stroke. It shouldn't be at 6 o'clock on a 2.5L; more like 4 o'clock.

jstiley1 02-01-2013 07:01 PM

Oh...crap...durn chilton

Xpress 02-01-2013 10:29 PM

Quote:

Originally Posted by Airboatingobx (Post 3281314)
Drop the tank and drain the gas then drain the carb, then put in a can of sea foam and around 5 gallons of gas and crank it up should run like crap till it gets the varnish out. Might want to go ahead and rebuild the carb or up grade and replace it with a motorcraft carb.

All 2.5L YJ's were equipped with fuel injection from the factory.

The OP (if the intake is still factory) will have a Throttle Body Injection unit. They were included from 1987 to 1990. 1991 to 1995 got Multi Port Fuel Injection.

jstiley1 02-04-2013 05:33 PM

Yah I didn't think that was a carb...I reset distro. But still no luck..however no more back fire..chug chug chug

brentd711 02-04-2013 07:33 PM

Pull a plug and make sure you have spark. If you do give it a shot of (fresh) fuel in the throttle body.

jstiley1 04-24-2013 10:03 AM

Hey all its me again....sorry it has taken so long to get back in here...i havent got to work on it much in the last 2 months...If it isnt one thing its another......
Latest work on jeep was...i pulled timing chain again and put it back on to make sure it was done properly...Still no luck....the jeep just cranks and cranks...if i put the plug wires on the cap the way they are supposed to it will crank then back fire thru intake ...if i move the counterclock wise one it wont back fire but wont start either.... just a rundown again of all the work so far..
NEW : distro, cap , rotor plugs, coil, and whatever you call the box the coil mounts to (ign. control maybe?) , crank pos sensor, timing chain ..
Also have drained tank added 5 gal new gas and changed oil and filter
As yall can see i have done a great job of throwing cash at it with no success...but not all in vein cause when it runs itll be happy..

jstiley1 04-24-2013 10:50 AM

oh yah one more thing... can i get a consensus on where the ROTOR needs to point at TDC...i have seen 4, 10 , 2 , 6 o'clock...if not ill try em all :)

Pukeolicious 04-24-2013 11:19 AM

Don't go by clock positions, just make sure it is aligned with the 1st cylinder's cable.

jstiley1 04-24-2013 11:37 AM

ok thank you...i have heard that too....im going to try it when i get off work...

jstiley1 04-25-2013 08:17 AM

Update: i pulled distro. set engine to TDC and got rotor pointing to 1 wire...and still no go....however back to backfiring out of intake every so often....i have read somewhere about possible stuck valve...??? thoughts? is there a way to test this

Fishnic 04-25-2013 08:22 AM

i assume you used the mark on the crankshaft pulley to determine TDC?

sevenservices 04-25-2013 08:40 AM

Quote:

Originally Posted by jstiley1 (Post 3680730)
Update: i pulled distro. set engine to TDC and got rotor pointing to 1 wire...and still no go....however back to backfiring out of intake every so often....i have read somewhere about possible stuck valve...??? thoughts? is there a way to test this

And make sure your at TDC of the COMPRESION stroke, not the Exhaust stroke. You can pull the valve cover and watch the rockers. Stroke 1, piston goes down w/intake valve open on cyl 1. Stroke 2, piston comes up and compresses the gas with both valves closed. (stop at TDC), stroke 3 FIRE, piston goes back down, stroke 4 piston comes up with exhaust valve open to let the burnt gasses out. If your at TDC of the exhaust stroke, its a no go...

And yes, test for a stuck valve with a compresion tester. They screw onto the spark plug hole, crank it over a few times and it should hold up compression. Do this for each cylinder, if one has no compression, you'll know there is a valve stuck.

http://www.toolsinstock.com/admin/images/77043.jpg


All times are GMT -5. The time now is 01:58 PM.