Welcome Visitor! Please take a few seconds and - Joined
- Aug 26, 2008
- Messages
- 1,094
- Vehicle Year
- 1994, 2001
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- Automatic
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- Failing is easy. Everyone can do it.
Okay. So far a large number of issues have been resolved..but some linger on like hitting a skunk with a nerf bat.
Basics:
1989 Bronco II, 2.9v6, 2wd, auto, insert comment here.
It was running decent a few months ago--And then things went down hill. It's always had a minor burp when I leave it for several days-- It starts very rough. But it always kicked over after a few rotations. Ran a touch rough..but always came through.
Recently we tackled the issue with coolant entering the left front cylinder. The old girl was blowing tons of white smoke after starting--the smoke would clear up after a few mins and then ran fine? We did the intake gasket and that stopped the white smoke dead in it's tracks. We get the usual condensation now when it starts--and then all clear
However the load stone that's been plaguing this engine recently? It starts extremely rough. It will turn over and start after several attempts---only to stall out..It does this several times...finally starts and runs very rough. After about 4-5 minutes? Idle returns to normal, runs smooth. This afternoon it returned to an old issue that it's not done in a while---Bad Surging right after starting. High idle....drops low.....kicks high...rinse and repeat. That normally clears itself up after a moment or two...
We attempted to track this down and replaced a few key parts.
a) The wiring harness was badly burnt up when I purchased the truck. The harness for the O2 sensor hit the exhaust pipe and shorted out the feed line for the heater. The result was a melt down of the first connector and all the wiring. While I did replace and splice in new wires? I've always considered this suspect---And sense the coolant sensor connector was brittle, along with the injector plugs? The harness was replaced with a better condition one from our local pick 'n pull.
b) The injectors....Ughhhhh... I've cleaned these stinkweeds twice. Got 'em to spray great--But they always seep. You can watch the fuel pressure drop like a hammer. Remove the rail---prime the fuel system...And watch fuel start to drip out and ooze out. Soooo.... Again pick 'n pull. We found a 1990 F series with a 300 FI L6. It had some pretty decent looking injectors. Plus as an added bonus? Once we started pulling the fuel rail from the injectors--- The system was still under considerable pressure. All 6 injectors didn't seep at all! Considering the truck clearly has been in the yard for weeks.... Just to verify it? I installed the injectors, primed the system... Gave it a short while to see if any seeping....none. Installed the rail, and while the starting rough issue is there still? The truck lost the "Bog Down" it was doing when you hit the gas at the stop light. She had some great pep back after that change out.
Some other data that may or may not be useful:
Vacuum after the truck finally starts up is 15in. And that's a rough 15in. (The needle does not jump--it stays steady--but you can hear the engine is struggling) Wait for it to settle down? And it nails 18in and idles fair. Unless it wants to start the surge crap--then all bets are off.
Fuel pressure is decent. Runs about 34-36PSI at idle. WOT and removing the vac line and the pressure hits over 42PSI. I did note when the engine was turned 'off'--the pressure was still dropping off slowly. Sense I know it's not the injectors this time--I do suspect the fuel pump or the support system's check valve may have seen better days. Do I feel the pump is bad enough to create these problems? Not really--I can (once things hit 'smooth' running) hold the engine at 2500 RPM. Pressure is good on the gauge, and the engine does not act like it is starving for fuel.
Plus during my test drives this afternoon...I nailed the gas and drove it under heavy load at 4500RPM. Smooth as silk. Not what I would expect if it was getting starved for fuel.
The truck could use a tune up in the future.---But the wires are still serviceable and the cap/rotor checked...no signs of carbon tracking I can see. Plugs are NGK V-Power and are only slightly worn.
That's about all the info I can think of. At first I was considering the front converter was getting plugged up after sucking/burning off the coolant for so long. Sure---that would explain the low vacuum when it finally starts. Had to dismiss it--A plugged converter would still allow the engine to physically 'start'---it would bog down after a few moments when the back pressure hits. Additionally a duff converter would strangle the engine once it's at temp as things 'expand' The engine is doing the exact reverse of that. Starts like crap and then runs like a bat outta He&& once it's warmed up.
This is kinda where I sit. Oh yes...No chance of the timing chain problems. I checked that when I first started this wing-ding. When I pulled the cap I took the advice and checked the timing chain for play. There's none. Move the crank--and the rotor moves instantly...(both ways...just enough to make sure no slop in the chain)
Ideas are welcome! I can relay if tests or checks have been done as things move along. I'm happy with the injectors--It didn't solve the large issue about the starting. But it sure cured the stumble it's had when I pull away from the stop signs/lights!
S-
Basics:
1989 Bronco II, 2.9v6, 2wd, auto, insert comment here.
It was running decent a few months ago--And then things went down hill. It's always had a minor burp when I leave it for several days-- It starts very rough. But it always kicked over after a few rotations. Ran a touch rough..but always came through.
Recently we tackled the issue with coolant entering the left front cylinder. The old girl was blowing tons of white smoke after starting--the smoke would clear up after a few mins and then ran fine? We did the intake gasket and that stopped the white smoke dead in it's tracks. We get the usual condensation now when it starts--and then all clear
However the load stone that's been plaguing this engine recently? It starts extremely rough. It will turn over and start after several attempts---only to stall out..It does this several times...finally starts and runs very rough. After about 4-5 minutes? Idle returns to normal, runs smooth. This afternoon it returned to an old issue that it's not done in a while---Bad Surging right after starting. High idle....drops low.....kicks high...rinse and repeat. That normally clears itself up after a moment or two...
We attempted to track this down and replaced a few key parts.
a) The wiring harness was badly burnt up when I purchased the truck. The harness for the O2 sensor hit the exhaust pipe and shorted out the feed line for the heater. The result was a melt down of the first connector and all the wiring. While I did replace and splice in new wires? I've always considered this suspect---And sense the coolant sensor connector was brittle, along with the injector plugs? The harness was replaced with a better condition one from our local pick 'n pull.
b) The injectors....Ughhhhh... I've cleaned these stinkweeds twice. Got 'em to spray great--But they always seep. You can watch the fuel pressure drop like a hammer. Remove the rail---prime the fuel system...And watch fuel start to drip out and ooze out. Soooo.... Again pick 'n pull. We found a 1990 F series with a 300 FI L6. It had some pretty decent looking injectors. Plus as an added bonus? Once we started pulling the fuel rail from the injectors--- The system was still under considerable pressure. All 6 injectors didn't seep at all! Considering the truck clearly has been in the yard for weeks.... Just to verify it? I installed the injectors, primed the system... Gave it a short while to see if any seeping....none. Installed the rail, and while the starting rough issue is there still? The truck lost the "Bog Down" it was doing when you hit the gas at the stop light. She had some great pep back after that change out.
Some other data that may or may not be useful:
Vacuum after the truck finally starts up is 15in. And that's a rough 15in. (The needle does not jump--it stays steady--but you can hear the engine is struggling) Wait for it to settle down? And it nails 18in and idles fair. Unless it wants to start the surge crap--then all bets are off.
Fuel pressure is decent. Runs about 34-36PSI at idle. WOT and removing the vac line and the pressure hits over 42PSI. I did note when the engine was turned 'off'--the pressure was still dropping off slowly. Sense I know it's not the injectors this time--I do suspect the fuel pump or the support system's check valve may have seen better days. Do I feel the pump is bad enough to create these problems? Not really--I can (once things hit 'smooth' running) hold the engine at 2500 RPM. Pressure is good on the gauge, and the engine does not act like it is starving for fuel.
Plus during my test drives this afternoon...I nailed the gas and drove it under heavy load at 4500RPM. Smooth as silk. Not what I would expect if it was getting starved for fuel.
The truck could use a tune up in the future.---But the wires are still serviceable and the cap/rotor checked...no signs of carbon tracking I can see. Plugs are NGK V-Power and are only slightly worn.
That's about all the info I can think of. At first I was considering the front converter was getting plugged up after sucking/burning off the coolant for so long. Sure---that would explain the low vacuum when it finally starts. Had to dismiss it--A plugged converter would still allow the engine to physically 'start'---it would bog down after a few moments when the back pressure hits. Additionally a duff converter would strangle the engine once it's at temp as things 'expand' The engine is doing the exact reverse of that. Starts like crap and then runs like a bat outta He&& once it's warmed up.
This is kinda where I sit. Oh yes...No chance of the timing chain problems. I checked that when I first started this wing-ding. When I pulled the cap I took the advice and checked the timing chain for play. There's none. Move the crank--and the rotor moves instantly...(both ways...just enough to make sure no slop in the chain)
Ideas are welcome! I can relay if tests or checks have been done as things move along. I'm happy with the injectors--It didn't solve the large issue about the starting. But it sure cured the stumble it's had when I pull away from the stop signs/lights!
S-
