BroncoII4x4.com

Hello everyone, I need some help with my BRONCO II '88 2.9,
It all started with alittle shacking while i was driving, it would start to choke like it wasn't getting enough gas. Sometimes it would run very rough and mostly choke only when driving on a highway at higher speed, In lower gear, low speed it was working better. But lately it was running rough even in lower gear, It all started very slow, and was chocking just alittle and now it wouldnt start at all. At one point that chocking was gone for a couple of days and i thought that maybe it was just water in my tank but when it came back it was even worse and now when i try to start it - it turns over but wouldn't fire up. Yerstaday after not starting it for almost a month - i decided to give it a try and turned the key- and omg it started, but it only lasted about 3 seconds and then it quit again Iam wondering if someone had similiar problem? please help if you have any kind of answer. Help is greatly appreciated. Thanks!

I dont know if this will help, and you should probably try other things first. bu I had a problem that when i got on the freeway after about 5 minuts the truck would start stuttering and i would lose about half my horsepower. I couldnt figure it out for the life of me. fought it for abot a year. then decided to go 5.0. after tearing out the 2.9 i tore it apart. I think the problem is that teh lifters had goten out of adjustmet which I guess isnt uncommon. anyways. thats my two cents. some other ideas are... fuel pumps, there are two, one in hte tank one on the frame. you should be able to hear them running with the key in the "run" position. thats all i got right now.

Check fuel pressure, if none check filter, if OK check BOTH pumps. If OK then check the vent hose from the charcoal canister to tank.

ECM ................. could be bad or plug bould be loose .... :hmmm:

from my understanding the reason for the lifters clanging and coming out of adjustment was misalignment in the lifters when the motors were produced, which causes excess wear on the camshaft and lifters causing them all to make the annoying clatter sounds we all had in the 2.9 liters..... it was an issue never fixed ....... thats why all the 2.9 liters make noise .... but its also the reason they all need to be adjusted from time to time..... i read it on a site from ford somewhere and if i had the link i would post it here but i cant seem to find it now, sorry for that, but that is a possibility with the lifters causing that ..... and this is the main reason i opted to do the 4.0 upgrade instead of rebuilding my 2.9 when it gave out,

TFI Module Resistance Test: (9)



The TFI module may be removed, and tested for resistance between terminals to determine complete failure. Often stock TFI modules only partially fail when engine temperatures get warm, and the vehicle runs rough then dies. The vehicle then restarts, and runs for 20 seconds then dies again. This is a defect, which affected ALL TFI modules before 1995, although some do not seem to be very problematic (this is often causes codes 14 and 18).

here is something i found you might want to know abaout it might just be the thing that helps you out .......

he info listed above came form a usefull page online ...
http://www.broncoii.org/techpages/eeciv/index.htm

TFI: Thick Film Ignition. A Ford Ignition module, which is found at the base of the distributor.

IAC Cleaning/Testing: (12)



The IAC is usually a cylindrical unit attached to the upper intake manifold. This unit electrically controlled by the computer, and allows air to flow into the intake at idle, bypassing the throttle plate. The extra air is accompanied by extra fuel to bring the idle up to proper speed, and when cold, allows a high idle condition. These units may become dirty, and need cleaning. Many idle and stalling issues tend to be blamed on these units. Cleaning is achieved by removing the electrical connector, and two screws holding it on. Once off of the vehicle, clean with throttle body cleaner (or a good carburetor cleaner). Continue cleaning until unit is clean, like new; reinstall unit. This is also a good time to clean the intake, and EGR ports (if applicable).

Testing may be achieved by bringing the engine to operating temperature, noting the idle speed (should be within spec). Unplug the unit’s electrical connector, and the idle should drop to about 650 RPM. When the unit is reinstalled, it should return to normal idle speed. If the vehicle does not idle at proper RPM (too low), there are no vacuum leaks, and the TPS calibration is correct, than the unit is most likely faulty.



FPR Testing: (13)



An essential part of the EEC-IV system is the fuel system. Often, the fuel system is blamed for faults which actually occur elsewhere; however, a simple test can test many components. A high pressure fuel tester must be connected to the fuel relief valve on the fuel rail (usually a Schrader valve). First relieve fuel system pressure, then attach the tester. Next, turn the key on (engine off) to prime the fuel system. There should be 36-42PSI of pressure. Start the engine. The pressure at idle should remain within the same range. Rev the engine a few times to ensure fuel pressure remains constant. Excess pressure usually determines a faulty FPR. Too little pressure could be the FPR, fuel filter, fuel pumps, or a leak.





personally i would check the ignition module, you said you had a new one put in, well i know if the part came from autozone....you probably got a bad part .... LOL..... dont buy electrical components there they suck ..... found out by replacing a starter 4 times i bought form them on a truck ... 4 times in three months ....... but i would almost bet its the ignition module mounted on the distributor....

oh and it could be the throttle positioning sensor, but it was covered in that link i posted....... you should find the problem somewhere in that site and i would print that for later use......

http://www.broncoii.org/techpages/eeciv/index.htm

well it always makes me wonder if the problem was found when no one responds to tell us if their problem was solved.... it might be i know several more things that would cause it not to run and could help with those ...... but i would need more details first