89 Ranger 2.3L 4x2 manual

Truck started & ran for 5 seconds then quit....so here's what I did:

Replaced ignition coil on the exhaust side which was cracked. Pulled 4 plugs on exhaust side, cleaned, getting spark. Confirmed spark with inline ignition tester. Fuel pump energizes when key is on, fuel at the rail (haven't checked pressure yet, but squirts out solid stream). Checked timing while cranking, 10 deg BTDC as specified. Checked compression, bit low but 90 psi on each cylinder. Pulled codes from EEC IV, faulty EGR--cleaned that and got that working. Checked one injector with test light, appears to be strobing while cranking, & can smell fuel after cranking. Have tried spraying gas & brake cleaner into intake while cranking but nothing. Tried starting with the throttle position sensor unplugged, cleaned grounds around computer but no change.

Going to replace plugs next, maybe spark is too weak? The replacement ignition coil did not have cylinder numbers next to the posts as the old one did--I am assuming the posts would not be in different positions and connected them to the cylinders as the old coil was connected...

EGR valve not completely sealed when the valve is closed...very small leak...thinking of taking this off to ensure no exhaust leaking back in.

Anybody have any thoughts on what else could be happening here or what to try next? Sometimes when it sits over night it will actually start for a second or two then quit, but lately not even that.

 

Compression is too low for cold start with gasoline but ether(quick start) should cause it to fire.
Contrary to the Movies it takes a bit of heat and a spark to ignite gasoline, compression heats up the gas so spark can ignite it

Only exhaust side coil works when starter motor is on, intake side spark starts when engine does.

'89 2.3l will have compression ratio of 9.0:1 so you should expect bout 160psi, that's with 1 spark plug removed from each cylinder to get good crank speed from starter motor.
But even if all spark plugs were in I would expect above 120psi with good battery and starter

90psi could mean timing belt is loose or off by 1 tooth


Firing order for coil packs here: Ford Ranger Firing Orders

If you have intake coil wires reversed then it could cause engine to stop once it comes on line by firing at the wrong time.

 

Did more checking, did find that the timing belt jumped 1 or 2 teeth. Corrected that along with 4 new plugs on the exhaust side (much better spark) and it fired effortlessly. Timing belt was tight though--had a difficult time getting it loose enough just to pull off and reposition the cam--what would cause it to jump time?

 

Good work on getting it running

A hard backfire when starting can cause it.

Belt could have a weak spot, rubber tooth/teeth that allows a slip

 

Maybe it's time to replace the belt ???
If an engine with a timing belt jumped a couple of teeth, then it may be damaged and stretched a bit.
Running a weak timing belt can break and cause valve damage.

 

Just so jaferrio doesn't panic, the 2.3l Lima engines, like his '89 Ranger has, is a non-interference engine, this means the valves and pistons don't share any space in the cylinder, valve fully open and piston at TDC won't touch.
Broken timing belt will cause engine to stop running but won't cause engine damage

 

A spin engine is what I call that.
Interesting, I'm glad you mentioned that, I would have though that a modern engine like that would not have been a spin engine.

 

Most rubber timing belt engines are non-interference but not all so better safe than sorry, because "sorry" in this case is very very expensive when you have to replace bent valves and/or broken pistons

 

I don't think my old B2200 was a spin engine, but when I replaced the belt in it I always carefully turned the engine by hand a few revolutions just to be sure.

 

You should never spray brake cleaner into an engine, that is way too strong of a solevant. Also if its chlorinated it wont ignite anyways