Well, Sorta anyway.

Finished up work on the engine today..Learned a few interesting tidbits along the way. First off? That engine is a bear to purge the air from. Upper hose felt warm, so I figured the air bubbles probably finally got out of the system. Next thing I know? Temp gauge spikes to the "L" in "normal"...and then dropped like a rock back to the "O". She must have been seething a bit before the last bubbles kicked out. (thankfully, it's got the new heads from world products, and did not blow any white smoke)

And yes...the white smoke problem seems to be totally "Gone" from our exhaust. The engine still has a knockey-tickey sound a bit on the heavy side when it's first fired up, stone cold. It settles down to a light lifter clatter which we can hear loud and clear coming from #5 or #6. Might have to pull that valve cover and re-do the valve lash. Failing that? Fair chance the lifter's are not pumping up as well as they should.

Ok...That brings us to the next problem. Actually this was one of the issues it had before the engine got torn down. (keep in mind? All the ignition system has now been replaced, except the disty itself, module, and coil...and it's got some large spark)

Idles a bit on the rough side....with timing set correctly? It only pulls 15-16 inches of vacuum. It had the same lifter chatter before the tear down, and the compression at that time was 180lbs average on all 6. Nothing out of specs of that by more then 5lbs.

If you kick the gas, warmed up and ready to go? It does have a stumble, but will rev up.

If you put 'er into gear? (drive or reverse) and get on the gas? The engine vacuum drops to 5"...and it just bogs down severely. It's acting like it can't breath. No signs of vacuum leaks, everything buttoned down nicely. New O2 sensor as well (no thanks to Ford for putting it where they did).

I've got a nasty idea the converters might be plugging up, or plugged up--we found some amazing loads of carbon all over the valves and intake. It's all cleaned up--and the old plugs where also badly carbon-caked as well. I have the feeling this was due to not having a working 02 sensor for a while. (it was busted off the pipe)

Fuel pressure is at 40lbs on the rail as well.

This seems a bit odd? It's the exact same problem we had before the tear-down. Granted it starts pretty decent with the new cap/rotor/wires/plugs. And there is no "check engine" light coming on either.

It just seems to bog itself down in gear---like it just can't suck air in-- That's the only way to describe it?

Any ideas are welcome at this point. I'm going to drop the cat-converters tomorrow (Sunday) and give them a visual inspection to see if they are plugged. If they are plugged? Well--they have to be replaced anyway--So I'll probably drill 'em out for testing purposes to see if we have a backpressure issue.

Suggestions always welcome!! And on the lighter side? The wipers fixed themselves LOL.

S-

 

Done alot...wheew

are loosing coolant??

have you done anything to the rod and main bearings or cam bearings?
could explain the noise you're hearing. definatly recheck the valve lash

other things to check:

as far as the temp goes...seems like the temp sensor (both of them, 1 for the dash &1 for the engine comuter) maybe bad. factory guages are notorious for giving poor to faulty feed back,,,seriously consider a good set of mechincal guages replace the thermostat with new ...its cheap.

the TFI or ignition module maybe a issue too....remove (you'll need a special wrench <$10) and take to the parts store and have them check it...run test several times.

clean the AIC considering the vast amount of carbon that was present prior to you starting ...could help the rough idleing

run codes

 

Not loosing any coolant as far as we can tell. Both heads are brand new ones from World Products. Main reason we changed out both of them? Once the engine got warmed up? It was spewing white smoke out of the tail pipe like a 'skeeter fog machine.

It was also running EXACTLY like it still does, both before and after the new heads were installed. Both problems appear to be separate from each other. While we have cured the white spew? The driving issues are at hand.

It's not on the road as of yet, so we are left running it around the folks back yard Weeeeeeeeeeeeeee!!!!

The thermostat is new of course, the one killer of the heads is over heating--and a common cause is a duff thermostat. It's been replaced with a 180 degree one. The fit was 100%, and it's listed as "optional OEM temp" by the auto parts store. The wax pellet is faced IN towards the intake.

Cam/main/rod bearings not checked at this time, and I honestly do not want to go through that LOL. Oil pressure on the gauge is actually responsive. Sits right up there when cold...when warmed up? Rests slightly lower and reacts with engine RPM.

Now one thing that I'm not sure of--this might be related, or a gauge issue? But the dash tach reads about 1500rpm to 2000 rpm to high. I dropped 'er into gear yesterday, the engine went to about 600 rpmish (guessing, it was low---but did not stall--heck, actually pretty damn smooth) And the tach still read 2000? Normally a tach gets a signal from the coil "t" terminal, but I noticed the module also has a tach line. Now if the computer is getting a wonky tach signal? That would screw up the gauge and the engines control.

So today is going to be some more testing. I've got a new fuel filter to install for the preventive maintain... Going to drop the cat's to see if they are plugged. (pretty sure all that white smoke didn't do much for the converters appearance) Then it's off to pull codes, and run basic computer sensor tests.

I'm not looking forward to the TFI module, if that's the issue. I'd love to kick the person that designed the disty under the air intake--and crammed it against the firewall. If it's bad? I'm going to pull that whole sob out of the engine, change it--and reinstall it. Might be easier on the back and hands to just eat the cost of a new upper intake gasket, then to attempt to remove the module in the truck.

I know the PO had this engine apart several times for teaching purposes. We are talking very clean (as in--no sludge build up anywhere) He teaches mechanics at a vo-tech center. I was expecting to see massive amounts of crud in the valve covers and under the intake gasket--That thing was as clean as a whistle.

In a way I get the feeling I'm back in college taking my tech courses all over again. The instructor would "create" faults, and have us try and figure out the problem and solution. Kinda like a broken o2 sensor--what would it do and why? (Yeah...replacing that made me want to install a 7/8" wrench into a fords designers fanny)

S-

 

Ok..Did quite a bit on the beasty today.


First off? Dropped the converters (what a fun job!! NOT) Shined a light through one end, through 'em both..and "I saw the LIGHT!" Put another way? They aren't clogged. We started it up without the converters in place--LOUD!! However the engine still bogged down, and put it into drive or reverse and give 'er some juice? Same story as before. So I put a new gasket on the pipe, and re-installed the cat's.

Ok, basic nonsense work:

Checked the TPS. We have 4.97vdc across the terminals 1 and 3. Throttle closed we have 0.93vdc. Ran the throttle up and down slowly? Nice and steady response, no jumps or signs of burned carbon track within the pot.

Did a base line test on the MAP sensor. Pins 1 and 3? Same, 4.97vdc. Pin 2? Steady mid-range reading with no changes. Figured it was bad? So I unhooked the line from the engine, instant stall out. Capped the engine port, and used a vacuum pump w/ gauge on the MAP. At about 15" the engine restarts normally--Anything higher or lower? And it stalls the engine out. Hooked the vacuum line back to the sensor (it's not plugged) And the engine idled and 'goosed' a bit rough--but no stalling.

Sounds like the MAP sensor is working normally, I figure it's sending back a "freq." to the EEC. hence why the voltage did not change, but the engine responded to the vacuum change.

New Fuel Filter also installed. That did seem to help a whisker, as the one that came off? "MOTORCRAFT" and it looked factory (or it's been there a heck of a long time)

Also did a full range test on the fuel pressure reg. At idle it gives about 34lbs of fuel pressure. (it was 40--however we did find a flaked out vacuum hose--it's been replaced.) Using a fuel pressure tester, and the vacuum pump? It reacts normally to changes in vacuum. Less vacuum? More pressure. More vacuum? And it reduces the pressure. No gas in the vacuum line either.

Now onto the dreaded EEC-4!!

KOEO: Code 11 All Ok!!
Memory stored: Nadda thing.
KOER: Kicked out the "Boo" code. (just when in the heck do you hit the brake pedal for the brake on/off test?)

That was it for the computer codes. I think---and I could be mistaken due to just about tripping over a cable--That in the first round of KOER, it pucked a code for "Rich" exhaust by the o2 sensor-- We repeated the tests 3 times to ensure nothing was missed--and the only code was the 11 for normal--and the BOO code. For what it's worth? The computer does control the timing fine, it did a nice job running up the idle/timing...reducing it back down...etc... Goose Test also came back 'normal'.

Everything computer wise appears to be working normally? But give this thing some gas? It freaks! Even driving it up onto the ramps? Had a slight 'load' and we had massive amounts of spark-knock out of the engine to get it up on the ramps.

On the lighter side? The lifters are normal now, the buggy ones finally shut up and are pumping up again.

Ok...at this time I'm fully clueless as to what in the hell is going on with this bronco II. Everything and every test I've thrown at it? Came back normal. New heads, good compression...Good air flow...etc.. It just runs like it's bogged down starving for air. Considering the air flow in/out of the engine is good? **shrug**

At this time I'm wide open for suggestions...I'm outta ideas, and won't be able to return to working on it until Thursday. The more ideas!!! The better!!

S-

 

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-

 

did you try the map sensor? could be the cause of all your problems

 

Yep, New one from Napa installed when we did all this fun.

Real kick in the pants. $40 to figure out the part is good, and they do not take returns on electrical sensors/switches. All to find out the auto multi-meter I already use? Has a "Freq." setting that could have told me it was good LOL.

(one of those days)

Due to work problems, I have not been able to do anymore work on it. I'll be able to bust a few things out for testing tomorrow (Thursday). Someone did suggest to check to see if the computer was in fact the right one for the truck. It's running "Fair" now, but just rich enough to create some serious eye watering when it's in the garage at idle.

I might kick the system to "Balance Check" and see if that points towards anything of interest. Right now I'm pretty much scratching my head?

S-

 

It has been my experience that watery eyes caused by the exhaust gases is caused by a lean condition. Dan.

 

Well...that puts a crink in the day. And that's a pain to research. (only found a couple google/yahoo hits on a general search.) I've always thought it was running a bit rich, and it was the unburned hydrocarbons in the air creating the eye watery bit?

S-

 

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-

 

My Bronco was having a similar problem when I rescued it from the scrap yard...Probably because of this problem...There is a fuel relay switch over kinda by the self test/air cleaner box, I tested this and found it to be intermittent, replaced it and it restored smoothness to the ol' 2.9er.

Just trying to help out a little.

 

Not sure at this point? The fuel pressure regulator was tested several times at idle only using a vacuum pump and a fuel pressure gauge set. I suppose I can rig in the gauge again, get it to repeat the problem (should be the easy part LOL) and see what the pressures are. If the relay is on the way out--normally they will start to internally "Arc", and that should translate to a reaction on the gauge.

Another thing to test, at least I already have the tool LOL.

I think I'm also going to go with the salvage yard EEC computer. It could have been one of those wires did manage to short out and do some minor damage to the input chip. Although I can't see any signs where the insulation was fully compromised? It might have kicked the computer if something did nail it. Only hold back? It does not show any codes for errors at all. Just keeps spitting out code 11 for everything.

S-

 

My 88 is almost doing the exact same thing. Starts and idles ok but when I put it in gear and give it gas, it's like it falls on it's face. No power. It's not a jerk like someone letting out the clutch to fast. It's slightly more suttle but not much. To me it's more like someone turning down the fuel pressure to 10 lbs when you step on the pedal.

I have not had a chance to diagnose it yet.

 

Minor update:

Repaired the burnt section of harness, turns out that's the part that feeds the inputs to the CPU. Also replaced the ECA with the one from the junker's yard.

I talked with one of my contacts down at Advance Auto. This guy's pretty decent and knowledgeable with most stuff. Turns out he's driven a few of the BII's and Rangers with that transmission, and he stated flat out that each one has bogged a bit when put into over-drive-drive...but runs a bit more peppy when in just "Drive" alone. One such was a BII that had the problem to the point the other emp. would put it into "Drive" and upshift to overdrive when he hit 50mph.

Is that useful information? Who knows?

The computer and wiring repairs didn't do much However I said heck with it, and removed (for about the 100th time) the upper intake. This time I was hell bent on pulling the injector rail and figuring out if this might be a fuel related issue, manifesting itself as more of a timing issue.

So the rail is pulled, and we did some tests. Just for an FYI!! DO NOT ATTEMPT WHAT I DID WITHOUT A HELPER AND A FIRE EXTING. THIS IS DANGEROUS!

Engine stone cold, ignition disabled. Rail sitting on top of the engine hooked up to the fuel lines. Hit the key to ONLY the on position to prime the fuel system. Used a small hook/scribe tool and a handful of paper towels and gently depressed each injectors "Pintle" valve (the tiny needle end that sticks out the end) System was primed after each test to ensure 40psi available.

4 injectors shot out a myst type fan spray. That's what I expected.

1 injector just kinda peed out at a moderate slow rate.

1 injector? Managed to get a bit 'wet' on the end, fully plugged.

Oddly enough? The peeing injector started seeping/leaking after the test. Figure something got into the valve and bunged it up.

Now I removed the wet one...and got a handful of gas and rust/crud out of the fuel rail for my efforts. The fuel sock which is visible on the 'in' part? Fully plugged solid with crud. I actually ripped the sock out of it, and it was packed like a small brick with gunk.

The wizzing injector that started to seep? That's on my desk now. It's also pretty caked with rust in the sock. I figure the other 4 are not far behind.

Now my wife asked me the magic question. Why would this create an issue only in closed loop, and not in open loop? My response?

In open loop, and just after starting the engine--the computer is working off very rich presets. The other 4 injectors are dumping in more fuel, due to the computer not being able to correctly read the O2 sensor. This could also explain why the idle after starting is a bit rougher then I'm used to.

Now when it goes into closed loop? The computer looks at all the sensors, and moves the injectors to fire in a more fuel managed method. With 2 of the 6 injectors not doing their job? The computer does not know that--and it's trying to manage the system. All the while with 2 cylinders getting to lean a mixture..

Now does any of that make sense??? Because I'm going to replace the blown apart injectors (Gotta admit...Yeah I'll take stuff apart LOL) And probably replace the fuel socks on the other 4 injectors that are still functional. There is nooooo way I can afford to replace all 6 injectors at this time. Little stinkers are very spendy on a tight budget. But I get the feeling this is going to clear up quite a bit of the problems.

If not? Back to the ol' drawing board------with a few more things checked off the list.

As for the gunk in the fuel rail? Gonna do it quick and nasty. With all 6 injectors off? Going to point the rail directly into a clean bucket...and nail the pump a couple of times. That 40lbs of fuel pressure should be enough to blast out the build up in the rail. And yeah...we will use extreme caution while doing so.

S-

 

Update:

I think we nailed it this time.

Replaced the two bunged up injectors, cleaned and installed new micro-filters on the other 4 injectors.

Now we still have a minor issue with the old 4 injectors "weeping" slightly when the system is under pressure, and it still is cold blooded to start up.

But once it got started up? It hit 'closed loop' and we backed it up and moved it forward. No issues at all. We also nailed the gas several times moving it...and this thing is taking off big time now. It actually lifted the front end up a good amount when I nailed it in drive.

The only side issue? We still have some smoke out the tailpipe....blackish/blueish and a bit stinky still. It's not to bad once it gets worked out a bit, I suspect it may have been burning off extra oil in the cylinders that where not firing correctly. (we coated the crap out of everything when we did the heads---with two of the 6 not getting enough fuel? Little chance of burning off the excess oil)

So it appears to be running pretty well at this point. A bit concerned about the smoke? However we also have under 1/2 tank of fuel...and a full bottle of Lucas injector cleaner, and a bottle of Duralube injector cleaner running in there at the same time. So time will tell a bit.

S-