Need some help with a 89' BII with a 2.9v6

[Tedybear]

Ok...Getting really flustered here. I'm looking for ideas.

Basics: Picked up a decent shape 89 BII with just about zero rust. Main issue I was told? White smoke from tailpipe, might need a tune up.

We took care of the white smoke, new heads from world products. We have zero sickening white smoke out of the exhaust when it is warmed up.

It did have a pretty severe issue with how the engine runs, figured it might be cleared up with a full tune up along with heads. Nadda.

What is it doing? In a nutshell. Cold Blooded, hard to start when cold. Once started? Shakes quite a bit. Does not seem to be mis-firing or skipping, just has the shakes? (need to double check motor mounts---but that's another issue to be resolved) Keep in mind EVERYTHING listed for what it's doing? Was also doing before I re-did the heads and resolved the cracks into the exhaust.

When it's in open loop, or closed loop the engine does the same thing. No power. After a short while, when it hits closed loop? The idle seems to settle down a bit--still rough, but better. Put it into gear? Idle drops to about 650ish for RPM. (hard to tell, dash-tach always reads about 2500 regardless of what the engine is doing) It's actually fairly smooth just sitting at that idle in gear.

Now in gear trying to get it to move? It bogs down extremely bad and tries to stall out. This is not on the road at this time, so our testing track (for lack of a better word) is kinda short? However put it into gear--hit the gas? And it just starts to shudder, bogs down, just sounds real sick. We put it up on a set of ramps for a test I'll list below, it barely made it up the ramps--all the while with some detonation/spark knock kicking up at a pretty good rate. Anything that puts this engine under any load? It buckles. Now it DID do this before the tear down! Just want to ensure no one states this is something I did while doing the heads-- (before anyone suggests it? new thermostat installed correctly as well)

Things we have done:

Compression Test: 180lbs average on all 6. None below or above a 5lb difference.

Full and complete ignition tune up: Plugs/Wires/Cap/Rotor/PCV/Fuel Filter/Air Filter good. Timing is set correctly! (yeah..I know how to use the SPOUT) With spout connected? Computer appears to modify timing accordingly. (had one small 'bounce'...but that's probably due to my super cheapo timing light having a hic-cup)

Replaced broken o2 sensor. Yeah...when the PO changed the transmission? He snapped the old one off the pipe.

Full test of Fuel Pressure Reg: 40lbs at start. 34lbs at idle. Reacts/Responds with a vacuum pump attached normally. NO fuel in the vac line.

TPS tested and working normally: 4.97 VDC at pins 1&3. Did sweep test using meter. Normal, no jumps or dead spots. Base line throttle closed? 0.93VDC

MAP sensor appears to be working: Hard to test, 4.97 VDC going in. Mid range steady voltage at pin 2. Suspect this uses a generated frequency to the EEC. Engine stable at 15 inches of vacuum applied (go figure? Correctly timed, and the best it manages is 15-16 inches of vacuum?) Go slightly higher/lower--and the engine starts to idle rougher. More then 4" difference from base line? Stalls the engine. Vacuum line is good.

All vacuum lines have been checked, PCV hose replaced due to some nasty cracks. No vacuum leaks detected. I expect none created during the install of the intake/heads--as this problem existed before the tear down.

Dropped the cat's and examined the converter material. A bit of carbon, but you can see through the honey-combs using a shop light. Nothing to suggest any clogs. Further note: We did a quick run test with the exhaust 'off'..same problem.

Computer codes: KOEO: code 11-system PASS.
KOER: code listed "BOO" test.
No codes stored in memory, kinda expected that--we had the battery unhooked for a week.

The computer does control the timing, as shown by the self-test. Goose test at first did kick up a "Rich" error at the O2. However we re-ran the test 3 more times, and only generated the "BOO" error. (when in the heck do you hit the brake pedal for that brake on/off test???)

If you can read this? Glad you stuck around!!

At this time I am totally lost and clueless. The computer seems to be "happy". Nothing is blocking air-flow?. The module on the disty appears to be fine--good spark and the computer does manage the timing.

Everything I've done, is considered basic maintaining the system. (the disty cap was factory---) And I've tested everything I remember how to test LOL. I'm a far cry from my tech's day as a mechanic---but this one has me totally confused?

The only things that might be clues? 15-16inches of vacuum on a correctly timed engine seem a bit low to me. Our '75 F250 manages at least 18-20!. Give this engine any load and some gas pedal action? Vacuum bottoms to 5". That's why I dropped the cat's, thinking a clog in the works.

I'm almost tempted to think the timing chain might have jumped a tooth--Or something else fuel related? Timing related? **shrug** I'm just not sure? I know the disty went back in exactly where it belonged when I removed it--lined up 100% with the marker lines I made, and the engine was not meddled with during the process.

I'm open to ideas on what/how to test....more or less how to get this ol' girl back to running normally. My job is cutting back, so I lose the company van--and I can't afford to drive the '75 F250 back and forth. (360 2bbl...runs great--but crap fuel mileage)

I'll be working on it again probably on Thursday and/or Friday to figure it out. I can't afford to much more $$ for throwing parts at it, so I'd love to get feed back on what/how to test--

Ideas welcome!! Thanks!!

S-

 

[IMenriched]

Well..you covered alot of ground

I was 1st suspecting the FPR...can you pull the small vacuum line off and see if any fuel dribbles out. At that time work/look it over carefully it might have a small crack.

It does seem like a vacuum leak might be culprit. concidering what you've checked
the Tech Library here has some very good vacuum guage diagnois help.

does it smooth out at all??....if not...double check the plug wire location/firing order.

might need to replace the temp sensor for the engine computer.

do you feel like it's lean or rich??

 

[Tedybear]

I'm not sure if the issues could be from it running flat out to lean, rich, or the computer is not controlling the timing correctly?

The FPR is dandy. I've read up on the horror stories behind when they fail and why. We did note a problem with the pressure using the old hose, it flat out stuck at 40 and did not move from there. So we replaced the cheese-master 5000 ford plastic crapola hose for a normal one. (no fuel in it) It became more responsive to the intake pressures once it was corrected.

There is no black smoke being spewed either while it's running--we where checking the exhaust every time it got up to temp to ensure we didn't have any white smoke LOL. We even made sure to re-use the tiny black cap/cover on the upper port of the PCV valve. (now at first I forgot it! Now that's a vacuum leak!) The PCV hose was also replaced, it was cracking apart at the mount.

Due to the PO test driving this thing all over creation with a missing o2 sensor? (and the wires floating in the breeze) We did a fair amount of 'de-carboning' things. The plugs I pulled out? SplitFires, and they where caked with carbon deposits. New set of NGK's installed, we've had excellent luck with the v-power series on several cars/trucks we have worked with. The disty cap? Totally Roached. Electrode wear was the worst I have ever found.

I did re-check the spark plug wiring to ensure it's 100%. Considering this truck I imagine was used as a "teaching tool"? If I wanted to plant a problem? I'd start with that---or if the disty was easy to get to? The pencil in the cap trick. Nothing seems to be out of whack with it.

This is the first time I've had one just confuse the snot outta me. Starts a tad hard--idles a bit rough, however you can still rev it up and it's somewhat responsive. The timing does advance as expected when it's reved up. Put 'er into gear? Idle drops to a normal low level fully warmed up, actually pretty smooth. Give 'er some gas pedal action?

Blahhhhhhh...... Put it under a load? Starts to bog down....Really give it a load? (like pulling up onto car ramps?) Detonation city, clatters..bogs badly...and just when you think it'll settle down? It stalls out like someone pulled the plug on it.

One would think running this poorly? It'd trigger something for a code?? Looks like I'll have to drive it around the yard a few more times and see if I can get the ol' girl to cough up another set of clues.

Currently the vacuum system appears sealed and normal. As mentioned we looked over and replaced anything the least bit suspect. The smoothest I've heard this ol' girl run? Is after it's in closed loop, and in gear at idle. Purred like a flippen kitten. Then you try to move it--and it reacts like ya just stepped on the kittens tail!

S-

 

[Tedybear]

UPDATE!! UPDATE!! UPDATE!!

Ok, me thinks it's time for an update.

Ok, spent the entire day working on the ol beast. Found one ignition problem that we figured should be all set, but it's still running like crap LOL.

Did some more basic testing this morning. Had my better half re-do the test in closed loop, put the truck into drive..and see what the timing does. Timing went right to 10d btdc, and STAYED there. Gave 'er a little gas, and the engine detonated a bit and stalled out (we are trying to keep the boom-booms for detonation as min. as possible during this). Ok, scratch me noggin' for a bit...no timing changes, and it defaulted directly to like the SPOUT is disconnected??? Put it back into park, no load on the engine..and the timing advances normally.

Also I used a mechanics stechacopethingie and listened to each injector. Happy enough, ticking away.....

So I went and bit the bullet, replaced the MAP sensor...very very slight difference---timing still not advancing while in gear with the accel on lightly. Said heck with it and pulled the upper intake and the disty.

We replaced the TFI module (which tested 'GOOD' at the auto parts store) and I lopped off the harness to the module and replaced it with a new pig-tail.

Now that seemed to do the trick with the timing. It now advances while in gear--in open loop. Closed loop? Yeah it's advancing--kinda "wandering" a bit, but it's at least reacting. HOWEVER while the extreme detonation issue went bye bye? In closed loop--in gear with a bit of pedal? It still bogs down, not as bad..and a touch of detonation (no where near as bad as it was---vast improvement) And both our eyes started to water something nasty!! In closed loop? It's now running to rich it seems. Not rich enough for black in the exhaust, just enough so we know it's an issue.

So we went from having no timing advance in gear, to having timing advance in gear--but the engine is loading up with to much fuel.

Gonna have to ponder this a bit more over the next few days. Considering the FPR is good, the injectors tick away nicely...one might be sticking open a bit? O2sensor is brand new, and the engine didn't throw any codes at us.

That's it so far....Looks like the upper intake comes off (again) and I'll have to dig into the fuel rail and injectors next. At least it's progress being made!

S-

 

[fordwheelinman]

does it have the right computer in it?

 

[Tedybear]

does it have the right computer in it?

I hope so.. Near as I can tell it should be the right one? However I'll probably do some research and see if I can look up the part ID number to verify it. I'm just happy the timing is now able to adjust itself while in gear--That cured quite a bit of the major problems. Just seems to be remaining issues with the air/fuel mixture while in closed loop operation.

S-

 

[fordwheelinman]

The reason i mention it, we put a 88 motor in a 90 bronco, both were automatics, both 2.9's. Didnt think anything of it. We ran it a week or so, no power, poor acceleration, really crappy performace. I cheked the calibrations on the computers with the parts guys at work, did not coincide, had to use the 88 copmputer with the 88 motor. Learning experience.

 

[dirtsquirt]

are u sure u have the plug wire all correct, sound like a fire order problem

 

[IMenriched]

From soup to nuts...you've coverd alot of ground....wheeew.

took more time to fully read what you have....

the only things that spring to mind is the pick-up coil inside the distributor. -reason being-, that you had the best overall change/improvement with the new pig tail for the TFI.... or in that same area the distrib gear is wore.

One other thing is that maybe in the past, that it was given a bad FPR, with it being a teaching tool, that the brake booster now has a bad seal and you're still have a minor leak in there...robbing from the FPR now that timing advance is better.

Have you rechecked the vacuum since the improved timing advance?? gonna take a guess that your getting better vacuum pressure now.

Last thing... in the wire harness... there Might be the an in line resistor for the coil/ ignition...was it working....bypassed?? mine had one but when I quized others here about it...some had it some didn't.

Ok another thing...seeing as it was a teaching tool....could the fuel cap not be functioning correctly, not letting it to vent the tank....causing it to over fuel?? and yes the computer may not be compatitable

or another part of the fuel return componets not hooked up/functioning correctly..making it now over fuel....or it could be just old gas burning off...and smelling funky??

maybe just caused more questions then viable answers...IDK

 

[Tedybear]

Right now I'll take any suggestions.

The computer does appear to be the one that came with the truck from just a visual check. (no yellow salvage yard marker) I know that does not mean a whole heck of a lot? But I'll have to make a return trip over to the garage to nip up the ID's off the computer, which should tell me exactly which one it is. Could be?

The engines vacuum did kick up from 15 inches to about 16.5 inches. Still nothing to write home about, but the oddball thing? In open loop, kicking the idle speed up a bit? It nails 18" with ease. Now I did clean and test the IAC, and that's working normally--as is the TPS, with 0.93vdc at closed--and it ran smooth as silk moving from closed-to-open-to closed. (my full time job is a field manager for an arcade company, and testing pots and controllers is part of the job).

The brake booster was checked yesterday, forgot to mention it? However it did verify working normally. We removed the vacuum line, and capped it at the intake. Problem still existed.

FPR's been checked several times LOL. No sign of fuel in the vacuum hose, gauged it at 40psi with no vacuum applied, and with manifold vacuum applied? (did this part with a vacuum pump) it dropped to about 34psi.

Gas cap's a good call--We didn't try that one yet.. Simple enough, just replace it with a new one. (I like the cheap and easy fixes...plus with gas theft in the area? We'd be better off with a locking cap anyway)

The disty appeared normal, but the one thing in the back of my mind is the fact that while reving it up a bit? The timing mark I made for 10d? While it was advancing as I'd expect? Every now and then it would make a fast 'jump'. Like the #1 cylinder fired off to soon for just a second--and then it went back to normal. However sense I'm using a $10 buck timing light with a cheesy cheap pickup? I still feel that's a fault with the timing light. I might break down and get a better timing light and compare results..if a better name brand light does the same thing? That would point to a mis-fire and right back at the disty. (cap/rotor/wires/plugs are all new, so that should not create a cross-fire)

Right now the only thing that really has me confused? It's running fine, in fact pretty good in open loop mode? It's only when it nails closed loop when warmed up that it starts giving us the watery eyes and rough running. Now all things being equal? Yes it needs a more 'rich' fuel mixture when cold, so the injectors--if not firing correctly? Would probably not show up as much when stone cold. But when warmed up? It should lean out the mixture for correct operation.

Not 100% sure yet...it took a while to nail the timing advance problem, that appears to have been probably a bad wire/contact that only showed up when the engine was under load and 'shaking' at that low idle speed while in gear.

For what it's worth? I did triple check the wiring to the plugs. At first I just did a direct swap--wire for wire.. Then I used the shop manual and firing order--started at #1 (lucky me...it was marked on the cap that came off!) And went around the clock checking each one.

What I'll probably do when I get some free time? Is 'rent' a different timing light using the 'rent-a-tool' program, and recheck the timing. If using a different light--all the sudden that "misfire" vanishes? I know my timing light is crap. If it's still there? Could be a worn disty shaft sending out mixed signals.

Thanks all for the advise. The more ideas the better--I've not worked on a EEC4 system sense the early 90's...so this is jogging up old brain cells not used in a long while.

S-

 

[fordwheelinman]

it running fine in one mode, then switching modes and being crappy definately sounds like a bad/wrong computer. Had the same problem at work on a newer model ranger. After a week i decided to check if the right one had been installed back in june for a no start. Checked it out with the parts information, came back as the wrong calibration code. It would rrun as pretty as could be until it switched modes then it was puffing smoke and burning our eyes. Id seriously check it out.

 

[Tedybear]

I'll check it out asap. Right now I'm hosed into working Sunday-Thursday for location closings. The boss keeps throwing these closings at me, and then asks "How's the replacement transport coming?". He didn't quite like my answer the other day "It'd be going great, if I could ever get a flippen day off!"

Something else I'll be checking into is that mystery timing burp. Figure it's time to purchase a decent timing light...gotta find out if there is truly a mis-fire...or if the timing light is a piece of crap.

So that gives me a couple of things to check that won't break the bank.

a) computer being hosed/wrong (should be easy to see if it's wrong)

b) Disty might have a worn bushing causing the shaft to wobble and create a mis-fire.

c) Fuel injectors may need to be rebuilt/replaced. Might have some sticking open slightly causing extra fuel to be introduced.

Heck, sounds like a fun way to spend a day off--if I ever get one LOL.

Thanks for the help!!

S-

 

[94 splash]

just a question.. what plugs u using

 

[Tedybear]

Same plugs we've always used, NGK V-Powers. We have had excellent luck with them in all of our cars and trucks.

Our last car in fact had 'autolites' and they flat out sucked. Very sluggish, however it was also a turbo'd 2.2

S-

 

[Tedybear]

Ok, this thing is really pi$$ing me off to no end.

Did some more work on it, actually pulled it out of the garage and attempted (key word-attempted) to drive it around the yard. No power, stalled *harshly*--like someone grabbed the engine.

Pulled it back (Ok, more like limped it) back into the garage...sure enough--The timing problem has returned. It's not kicking to base 10 and staying put while in gear. It's attempting to advance under engine load. You can goose this engine while out of gear until the cows come home--and it's highly responsive! Put it into gear? Blahhhhh.

Did find some problems hidden, which I hoped would be the cause. Seems a few of the wires in the harness, about 3" from the 3 connectors (the two gray ones, and the black one) managed to overheat and melt into each other slightly. Found the same problem on all 3 sections of the harness. Now I did carefully pull the wires apart, made sure none of the wires where shorted or open...Started it...Again--idles great!! Put it into drive? Sameeeeeeeeeee problem.

I picked up 12' of primary wire and a box of connectors. I figure at the least I can patch in good wire to replace the wires with the burnt insulation.

Now as a side bar note? I did notice this problem has a very interesting quark.

Park: idles and revs ok
Reverse: Attempts to stall, recovers and bogs down.
Neutral: Idles and revs ok.
Drive-O: Attempts to stall, somewhat recovers and then won't move much before quiting.
Drive-normal: Attempts to stall---However it's a bit more smooth then in overdrive-drive?!?!?
Drive-all other low gears: Same as drive normal.

Seems if you put it into "OD"? The problem gets only slightly worse then if its in normal "D". Not sure what could be going on at this point?

It still wants to hunt a bit for timing, base timing checked again and good--vacuum's still maintaining 16". Goosed the throttle in park? Vacuum drop to 3"...kicked to about 23"...returns to around 16-17". Does so as expected. Just seems like if the computer would bump that timing up a bit? The vacuum should nail about 18"---and it should be better.

There is also an random "pop" out of the exhaust I didn't notice much--But I noted it today. Due to the vacuum readings being steady, and not showing signs of a sticky valve or burnt valve? I'm tempted to think it might be running a tad rich, and when it corrects? Might be popping off some unburned fuel in the exhaust pipe. It's not a back-fire...just a random "pop".

At any rate. Local salvage yard does have a matching CPU for the truck for $30 bucks. He wants a bit much for the pigtails for the connectors, so I'm going to re-wire them and correct that. I might just say screw it and drop a EEC4 computer into it and see what happens. I've already wizzed away a large amount of $$ on sensors that didn't do the trick... Just wish I knew why this thing can't work the timing correctly while in gear?

I can see what it's doing with a simple stall test---Timing hits about 18-20 advance--It starts to bog down---and it lowers the timing to almost the base (probably about 11-13btdc)...and sits there while the engine struggles--and finally just seems to "lock" and stop. Picture someone dumping the clutch if they didn't know how to drive a stick--that's how it's quiting.

S-