2.9L poor engine performance.
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From: Southern California
2.9L poor engine performance.
I recently purchased a 1987 Bronco II, V6, 4wd, 5speed trans., w/138,000 miles that has some engine problems.
I’m unable to get the engine to perform much past the lower/mid rpm range, it just flattens out, as I have no experience with the 2.9 V6 can anyone point to possible causes ??
This is my first post so I hope I did this right.......
Thanks for any help, Terry
I’m unable to get the engine to perform much past the lower/mid rpm range, it just flattens out, as I have no experience with the 2.9 V6 can anyone point to possible causes ??
This is my first post so I hope I did this right.......
Thanks for any help, Terry
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From: UT
2.9L poor engine performance.
When was the most recent tune-up?
Start with some basic diagnostic tests.
Check the PCM for trouble codes in both the key on engine off and key on engine running tests. Refer to any good manual or website (I like www.dalidesign.com/hbook/eectest).
Check the fuel pressure. A complete fuel pressure check will include leakdown and high RPM tests.
Check the timing. As part of the KOER test, the PCM tests it's ability to advance timing, so you might do this as part of the other computer tests.
Start there, and see where it leads.
Start with some basic diagnostic tests.
Check the PCM for trouble codes in both the key on engine off and key on engine running tests. Refer to any good manual or website (I like www.dalidesign.com/hbook/eectest).
Check the fuel pressure. A complete fuel pressure check will include leakdown and high RPM tests.
Check the timing. As part of the KOER test, the PCM tests it's ability to advance timing, so you might do this as part of the other computer tests.
Start there, and see where it leads.
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From: Southern California
2.9L poor engine performance.
Thanks for the reply, a complete tune up w/filters was already planed, the fuel pressure was on my list, but I didn't consider the computer controlled advance at all "thanks".
There aren't any flashing error lights showing, but I'm not certain what works and what doesn't as I just got the vehicle.
I also heard that it has two fuel pumps a low pressure in the tank and a high pressure on the frame, I had planned to replace the filter, I believe there is just one on this unit, in the tune up.
Thanks again for the input, Terry
There aren't any flashing error lights showing, but I'm not certain what works and what doesn't as I just got the vehicle.
I also heard that it has two fuel pumps a low pressure in the tank and a high pressure on the frame, I had planned to replace the filter, I believe there is just one on this unit, in the tune up.
Thanks again for the input, Terry
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From: UT
2.9L poor engine performance.
Originally posted by terrysmail
There aren't any flashing error lights showing, but I'm not certain what works and what doesn't as I just got the vehicle.
There aren't any flashing error lights showing, but I'm not certain what works and what doesn't as I just got the vehicle.
And, my '87 has two fuel filters. One between the tank and the high pressure pump and one after the high pressure pump.
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2.9L poor engine performance.
hey terry........my stocker 89 pulls hard for a six when floored...4x2 here with the same tranny as yours. when i first found this forum i went back through all the past threads looking for information......a huge help. good luck
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From: Southern California
2.9L poor engine performance.
Thanks, sometimes it seams as if diagnosing a problem is part of the fun of repairing vehicles, that is if you can find the problem before it wears you totaly down.....
I did look through the prior posts but didn't find to much on this problem, maybe that means it will be to hard to find, let's hope.....
Thanks for the reply, Terry
I did look through the prior posts but didn't find to much on this problem, maybe that means it will be to hard to find, let's hope.....
Thanks for the reply, Terry
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From: Monument, CO
2.9L poor engine performance.
A clogged cat could also be a possibility. Don't forget to pull the SPOUT connector when you check the timing.
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From: Monument, CO
2.9L poor engine performance.
SPOUT = SPark OUTput (or something like that). The computer controls the timing advance all the time in these engines, so in order to check the 'base timing', you have to take the computer out of the picture. The SPOUT connector is basically a little jumper that when removed, disables the computer's ability to change the timing.
So you warm up the engine, turn it off. Pull the spout connector out. Restart the engine and set your timing to 10 degrees BTDC. Once you're done, you turn the engine off and plug the connector back in. If you check the timing again with the SPOUT in place, it will be way up there, like around 30 degrees or so.
I have a photo on my laptop of the spout connector on my B2. I'm on the other computer now, but can send the photo if you need it.
So you warm up the engine, turn it off. Pull the spout connector out. Restart the engine and set your timing to 10 degrees BTDC. Once you're done, you turn the engine off and plug the connector back in. If you check the timing again with the SPOUT in place, it will be way up there, like around 30 degrees or so.
I have a photo on my laptop of the spout connector on my B2. I'm on the other computer now, but can send the photo if you need it.
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From: Southern California
2.9L poor engine performance.
Thanks, something else I was unaware of, I'm glad I bought a manual it sounds like I'll need it, now if it would just get here..........
Terry
Terry
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2.9L poor engine performance.
When mine ('86 2.9L FI) was doing the same thing I went through a new set of injectors, all the fuel filters/air filters, O2 sensor, etc. before figuring out what my problem was...
The little splice hose between the in-tank low pressure fuel pump and the outlet pipe (main fuel line) had rotted away. The low pressure pump was pumping gas directly back into the tank, and the high pressure fuel pump was having to suck its fuel supply directly from the tank, instead of being fed by the low pressure pump. New splice hose, no more problems.
The little splice hose between the in-tank low pressure fuel pump and the outlet pipe (main fuel line) had rotted away. The low pressure pump was pumping gas directly back into the tank, and the high pressure fuel pump was having to suck its fuel supply directly from the tank, instead of being fed by the low pressure pump. New splice hose, no more problems.
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From: Dyer TN
2.9L poor engine performance.
Originally posted by mrshorty
I just learned a few weeks ago that Ford didn't put a functional "Check engine light" into the BII's until '88.
I just learned a few weeks ago that Ford didn't put a functional "Check engine light" into the BII's until '88.
. *****
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From: Muskogee, Oklahoma
2.9L poor engine performance.
Yea, not much on power huh. Thats the same reason I'm putting a CARBURATED 302 into mine. ECM PCU HIGH PRESSURE LOW PRESSURE CHECK LIGHTS PCM CAT SPOUT EGR INJECTORS MULTIPLE FILTERS COMPUTERS The hell with all of that bull**** that can go out. I have enough problems without a computer flashing 32, 64, 44 to tell me a map sensor if malfunctioning or perhaps the speed distance sensor. All that crap is a means of the factory to make the average home mechanic obsolete and force us to take our vehicles to the dealership for service. Other than that, yea check for proper timing, make sure fuel pressure at the rail is in the right range, and make sure your getting good fire. Make sure the exhaust isn't clogged anywhere, unbolt it at the cat and test to see if power is returned (yes it will be loud). If everything above checks out test the compression, plugs, air filter(first), And if all that fails, locate the computer generously apply a 16 lb. sledge hammer to it until it gives up. Or go to work at a ford dealership. Im bored
Last edited by Ken00; Jul 29, 2003 at 12:28 PM.