Author Topic: The eternal question...why won't my 2.5 start and run  (Read 1039 times)

0 Members and 1 Guest are viewing this topic.

seedless61

  • Guest
The eternal question...why won't my 2.5 start and run
« on: April 06, 2008, 09:21:09 PM »
I feel like i'm in AA. Hi my name is (******) and my four banger jeep comanche won't start and run. Turns over but no fire. Got it for an affordable 200 bucks but because the previous owner couldn't get it to start lol. New crank position sensor and ICM later it still gets no runnin. Put a timing light on it and it shows spark. Turns over merrily. Coughs once in awhile but no run  :'( Any ideas guys i can try?

jrollings

  • Guest
Re: The eternal question...why won't my 2.5 start and run
« Reply #1 on: April 06, 2008, 10:00:37 PM »
have you got fuel and compression? if u have all 3 it has to start. make sure you have good spark at the plugs and make sure you have decent compression with the lowest reading being 20% of the highest.

Offline aw12345

  • Member
  • Posts: 3065
    • my jeep picture page
Re: The eternal question...why won't my 2.5 start and run
« Reply #2 on: April 06, 2008, 10:06:34 PM »
If the spark is good and fuel is supplied to the engine, and you chacked compression. its time to look for exhaust restriction or maybe a jumped timing chain. exhaus restriction to the point where it will not run is easy take the oxygen sensor our or loosen the exhaust pipe at the manifold. Oxygen sensor is easiest it should idle once it can get rid of some exhaust gas
2006 Jeep Wrangler TJ SE
2004 Jeep Wrangler TJ SE

Offline jfrabat

  • Gargantuan Mango Tree Mechanic®
  • Member
  • *
  • Posts: 3676
  • Finally USING the Jeep!
Re: The eternal question...why won't my 2.5 start and run
« Reply #3 on: April 07, 2008, 07:19:12 AM »
You may also want to check that the spark plug wires are connected in the right order; since did not do the connection, the previous owner may have connected them in the wrong order, which would cause the engine not to start...  It's probably not this, but worth taking a look at it anyway.
'94 YJ 2.5L with 4" RE lift, Superwinch EPi9.0, FoMoCo e-Fan, SD30 and SD35 w/ARB-5.13, 165A alt., 33" BFG KM2 on 15" AR wheels, Sony sound system, Pavement Ends Hardtop, Hydroboost

Offline oldjeep

  • Member
  • Posts: 1800
    • www.Oldjeep.com
Re: The eternal question...why won't my 2.5 start and run
« Reply #4 on: April 07, 2008, 07:26:59 AM »
Another thing to check would be to pull a plug and actually take a look at the spark.  You can trigger a timing light with next to nothing, there still could be bad plugs, coil, cap, rotor.
Chuck P
The clowns'? Oh, yeah, the clowns. We fight them too — entire armies, spilling out of Volkswagons. We do our best to fight them off, but they keep sending 'em in!
94 YJ - gone
98 ZJ - sons truck
97 TJ - daughters project

www.oldjeep.com

Offline neale_rs

  • Member
  • Posts: 3583
Re: The eternal question...why won't my 2.5 start and run
« Reply #5 on: April 07, 2008, 09:15:46 AM »
Make sure your fuel pump is running.  You can press that valve on the fuel rail and see it you get a squirt of gas (into a rag).
'95 YJ, 33 x 12.5 mud tires, RE 4.5 ED lift, Atlas 4 speed, rear D44, ARBs front and rear, 4.56 gears, 8000# winch