Fuel pressure and spark good, but no start...

[mnewland1]

-My 1989 XLT with a 5.0 had an AWFUL surging and would die at stop lights, and these symptoms would get worse as it heated up. Finally, several days ago, it crapped out on me as I was rolling through an intersection, luckily I had enough momentum to pull in to an alley way, but after much unsuccessful attempts to start it, I had to get it towed. Thank God for AAA.

-After some detective work, I found that there was no spark coming from the ignition coil. After some great help, thanks to this page...

http://easyautodiagnostics.com/ford/4.9L-5.0L-5.8L/ignition-control-module-tests-3

I narrowed it down to the distributor- mounted IGNITION CONTROL MODULE. I replaced the module, and even installed a new coil for good measure, now, I get a strong spark.

-Next, I test fuel pressure at the rail. Between 38 and 45 psi. Looking good right?

Still no start. I have a good battery and starter seems to work fine so it turns over GREAT, but no start. Doesn't even sound like it WANTS to start.

I spray carb cleaner into the dual, vertically-mounted intake and still NOTHING. This made me disregard injector pulse. Because with it should start momentarily with enrichment in the intake right?

-So, with my limited mechanical diagnostic abilities, I've narrowed it down to timing, compression or spark (ALL of the plugs are so bad they will not fire, even though they receive signal). But I turned the distributor rotor back to where it was already marked, shouldn't it be atleast CLOSE to in-time? And also, even if there is a head gasket breach and loss of compression, shouldn't the damn thing atleast TRY to start???

Please help. Any would be appreciated!

-Matt

 

[nelbur]

If your plugs are so fouled they will not fire, replace them, and use the plugs recommended by ford.   Badly fouled plugs can shut an engine down.   The recommended plugs will have the correct heat range to generally keep them from fouling.

 

[miesk5]

Yo,Timing Adjustment in Ford EFI Engines; MIESK5 NOTE; Spark timing that is ******** from specification may increase exhaust gas temperature and shorten catalyst life. Refer to the following procedure for service details. a. Check spark timing. Check base timing with spout disconnected.

Set base timing to the specification on the vehicle emission decal.

b. Check computed timing with spout connected.

NOTE: COMPUTED TIMING IS EQUAL TO BASE TIMING PLUS 20° BTDC ± 3°.

Use the ignition key only to start the vehicle. Attaching a remote starter might disable or initiate the start mode timing after the vehicle is started..." READ MORE

Source: by Ryan M (Fireguy50) at http://web.archive.o...ction.com/?p=71

For timing specs, see:

Vehicle Emission Control Information (VECI) Decal

underhoodvac.jpg

#1 cylinder depiction

by Ron's Beast:

http://broncozone.co...-1423516996.jpg

See hot links at

http://broncozone.com/topic/24834-how-to-set-the-timing-of-351w/

Is check engine light

On?

Try a Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe19

http://broncozone.co...7&mode=threaded

Some basics;

The engine temperature must be greater than 50° F for the Key On Engine Off (KOEO) Self-Test and greater than 180° F for the Key On Engine Running (KOER) Self-Test.

See hot links and more at

http://broncozone.com/topic/14269-code-reader/?pid=74587&mode=threaded

 

[mnewland1]

If your plugs are so fouled they will not fire, replace them, and use the plugs recommended by ford.   Badly fouled plugs can shut an engine down.   The recommended plugs will have the correct heat range to generally keep them from fouling.

Absolutely. I am going to change plugs and wires for sure.

Wow that's alot of good info!

Thankyou guys so much. I will report back when I get her fired up!