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I have a 89 EB (130,000 miles) with a 302 and an AOD. I have been fighting a pinging and surging problem for months. It idles fine, but under cruising conditions with a mild load is when it goes crazy (sometimes). This is what I have done so far: plugs, wires, cap, button, both fuel pumps, fuel filter, injectors professionally cleaned, egr valve replaced, egr sensor replaced, egr vacuum regulator replaced, timing is at 10 btdc with the spout out, fuel pressure checked, IAC cleaned, TPS checked, intake and throttle body removed and cleaned, checked for any vacuum leaks (none found). I have ran the codes about 6 or 8 different times. The only code that I am currently getting is 34 KOEO (DPFE problem). Just about everytime I run the codes I replace whatever it shows wrong, but I am tired of spending money without fixing the problem. I have ran 93 octane down to 87 octane it does not effect the pinging and surging. ANY help will be appreciated.
 

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The Anti Yam!
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seayya said:
I have a 89 EB (130,000 miles) with a 302 and an AOD. I have been fighting a pinging and surging problem for months. It idles fine, but under cruising conditions with a mild load is when it goes crazy (sometimes). This is what I have done so far: plugs, wires, cap, button, both fuel pumps, fuel filter, injectors professionally cleaned, egr valve replaced, egr sensor replaced, egr vacuum regulator replaced, timing is at 10 btdc with the spout out, fuel pressure checked, IAC cleaned, TPS checked, intake and throttle body removed and cleaned, checked for any vacuum leaks (none found). I have ran the codes about 6 or 8 different times. The only code that I am currently getting is 34 KOEO (DPFE problem). Just about everytime I run the codes I replace whatever it shows wrong, but I am tired of spending money without fixing the problem. I have ran 93 octane down to 87 octane it does not effect the pinging and surging. ANY help will be appreciated.
1. I coulda swor I read a thread almost identical to this a few days ago by a diferant user. Was it you?

2. Was 34 on KOEO or was it fom Continuouse memory?
 

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Virtually same set of conditions last month with my '89 302 Aod. Exception being, my BKO fouled #8 spark plug with carbon within a couple of hours at highway speed on four different occasions.

Performed compression check and leak down test, both failed at the home garage. Had fleet shop double check my work. #7 and #8 failed compression test again. One observation that has surfaced without me asking seems to be the relationship of the pcv to the # 8 cylinder.

Now awaiting crate engine for a heart transplant.....I hope you do not have to go this route as well.

Give some serious consideration to the intake and plenum gaskets for the %*&*&^*&^mn hidden leaks.
 

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Discussion Starter #4
Gacknar, was not me that posted the other day. 34 was KOEO.


Bronomeaux, I have not done a compression check yet, but I can say that all 8 plugs that came out of my bronco looked the same and looked like they were burning clean (a light gold color).
 

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Seaya-

Just a couple of more items. My truck has 126,000 for mileage. I do not know maintenance history for the first 100K. Another item that I omitted was a worn distributor gear that really helped this pinging under a mild engine load at 60-65 mph once the gear was replaced. This is almost the same set of symptoms for the same year model with same power train. Scarry, huh?
 

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Discussion Starter #6
broncomeaux,

yea it is scarry. I do not know the service history of mine prior to 128,000 (bought it in Dec. 05). Sometimes I wish I would have kept my stang, but oh well. I have been told that it could be the timing chain as well. But I can not understand why it only does it sometimes (more often than not though).
 

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The Anti Yam!
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34 (KOEO) = PFE or EVP circuit above the closed limit of 0.67 volts.
You got either a bad EVP or some bad wiring.

Test the EVP
http://fordfuelinjection.com/index.php?p=35


This question is gonna sound weird but bear with me.
What weight oil are you running?
 

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Seayya-

I forgot to disclose the timing chain replacement:banghead.
I forgot to disclose the egr assembly replacement:banghead .

FWIW try the distributor gear check before the timing chain, unless it is water pump time for you. The new gear made a significant reduction in the pinging.
The timing chain did not show much slack/wear.

It was at this stage the decision was made to start the planning for a engine swap. A worn distributor gear will likely be an indicator of a worn cam and so forth.

The engine degraded a little faster than I wanted.
 

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Discussion Starter #9
Gacknar,
I will check the EVP even though it is only about 3 weeks old. It is possible that I might have bought a bad one. Wiring checks out fine so far. I have checked connections and breaks in the wiring, but not ohmed them out though. I run Castrol GTX 10w/40.

Broncomeaux,
I will check out the gear first since the pump is new. The water pump, along with the radiator, fan, fan clutch and thermostat are fairly new. All this stuff was replaced prior to me buying it in Dec. 05.
 

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FWIW-These symptoms were diagnosed through the EEC and systematically repaired or replaced. I did not just start throwing parts at the symptoms.
 

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just a lil thought for you. it cost nothing but a lil time. try this: seperating no.8 plug wire from the rest and run it all the way down the valve cover by itself and around the back of valve cover to no.8 plug. dont let this wire cross another in its route. i had the same problem with mine and changed the pcv valve location to the plenum and seperated that wire and it fixed it.

as for the new crate engine: my question is, if your old engine did this, then wont the new one do the same thing? no.8 cylinder is run lean by 2 reasons. jumping fire and prematuraly firing or vaccum leak at the pcv valve. no.7 and no.8 cylinders fire in that order and will jump fire and burn up the plugs and pistons. i know this, cause i got one that did it. did a stock rebuild, top to bottom on the engine, put it back in, guess what? same problem, pinging and surging. isolated the wire and changed the vaccum on pcv, it was fixed. i will dig for the article that i found while working on mine and see if i can post the link to it.
 

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j w griffith said:
just a lil thought for you. it cost nothing but a lil time. try this: seperating no.8 plug wire from the rest and run it all the way down the valve cover by itself and around the back of valve cover to no.8 plug. dont let this wire cross another in its route. i had the same problem with mine and changed the pcv valve location to the plenum and seperated that wire and it fixed it.

as for the new crate engine: my question is, if your old engine did this, then wont the new one do the same thing? no.8 cylinder is run lean by 2 reasons. jumping fire and prematuraly firing or vaccum leak at the pcv valve. no.7 and no.8 cylinders fire in that order and will jump fire and burn up the plugs and pistons. i know this, cause i got one that did it. did a stock rebuild, top to bottom on the engine, put it back in, guess what? same problem, pinging and surging. isolated the wire and changed the vaccum on pcv, it was fixed. i will dig for the article that i found while working on mine and see if i can post the link to it.
JW-Your post and comments are timely. I assume your post was sent in response to my statements about a crate engine. Relocating the pcv in the new engine to the plenum is one of the objectives I'm looking into.
How did you modify the vacuum on the pcv, if I can ask?
 

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Discussion Starter #14
J.W.,
Thanks for the link. I will isolate the #8 wire by itself, and will be doing a compression check tomorrow.
 

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well.....i removed a vaccum cap on the tree on the plenum where the brake booster plugs on, put the vaccum cap on the vaccum on the back where the pcv was hooked. i used a piece of fuel line and routed it through a hole in the plenum and under it to the pcv and just clamped it so it wouldnt leak. its not hard at all just takes a few minutes of your time to make it look neat. it is effective though. i cant find the wiring diagram that i looked at as far as the isolating of the wire. i think ford actually put the diagram under the hood of the newer models like 95 and 96 f series and broncos. my cousin had a 95 f 150 that had the routing of the wires under the hood on a sticker. so, obviously, ford knew they had a problem and tried to correct it on later models. see if you can get someone to get a pic of their sticker and you'll see what i mean. sure hope this helps, i had to learn the hard way.
 

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I was the one in the other post. And no one has replyed after fixxing A few things with no luck, I'm goign to follow this one though, never thought about the wires though. And my truck is E40d 92 so it couldn't be me.
 

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i also found this too.....
1. Cross-fire on 1987 to 1993, 302 Ford engines. If the number 2 & 4 or the number 7 & 8 spark plug wires are located nexted to each other, the plug wires will induce each other to fire at the wrong time, causing piston, cylinder head and head gasket failure.

2. It is common on the 302 cubic inch engines, for the exhaust cross-over passage to crack on the bottom side of the intake manifolds. If this happens, exhaust gases will enter the crankcase and contaminate the engine oil, causing bearing and crankshaft failure.

3. Intake manifold coolant and vacuum leaks have been found to be quite common on 302 cubic inch engines. Apply a 1/8 bead of silicone sealer in the four corners where the cylinder heads meet the cylinder block. Install the intake manifold side and end gaskets, then apply a 1/16 bead of silicone sealer in the four joints formed by the gaskets. Mount the manifold and torque the bolts in sequence, , to 15-20 lbs.ft. Re-torque the bolts in sequence to 23-25 lbs. ft. and after the engine has reached operating temperature, re-torque the intake manifold one more time.
 

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+1 on the crossfire, had this on a 351W with 5 & 6... have this now on my 302 which I just did the wires on... just hadn't had time to lookup firing order and re-arrange the wires...

+1 on the intake for SBF as well... and re-torque and re-torque and re-torque.. especially on a built motor..

Tank92, have you just put wires on the truck? re-routed the wires? be careful man make sure you route them correctly.
 

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j w griffith said:
well.....i removed a vaccum cap on the tree on the plenum where the brake booster plugs on, put the vaccum cap on the vaccum on the back where the pcv was hooked. i used a piece of fuel line and routed it through a hole in the plenum and under it to the pcv and just clamped it so it wouldnt leak. its not hard at all just takes a few minutes of your time to make it look neat. it is effective though. i cant find the wiring diagram that i looked at as far as the isolating of the wire. i think ford actually put the diagram under the hood of the newer models like 95 and 96 f series and broncos. my cousin had a 95 f 150 that had the routing of the wires under the hood on a sticker. so, obviously, ford knew they had a problem and tried to correct it on later models. see if you can get someone to get a pic of their sticker and you'll see what i mean. sure hope this helps, i had to learn the hard way.
Is this what your looking for?
 

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Wow thanks for that picture, I'm going to get some more wire clips (lost some and some never were there) hopefully it helps!
 
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