engine problems 1988 B2

[greenjeepmax]

hello everyone i just recently purchased a bronco 2 and havin a hell of a time trying to troubleshoot my engine problems. the motor only seems to run when its ice cold so i replaced the engine coolant temprature sensor and still soon as it gets warm it dies and doesnt restart. it does run well over 2000 rpm but getting it past that take the motor a while.
any one else have a problem like this?

ps it looks to have a new IAC sensor too

 

[greenjeepmax]

any clue anyone????

 

[virginiakid]

Did you pull any codes off of it?

If you have a cracked head or bad head gasket, you will have more performance issues once the engine is up to temp. Any evidence of water in the oil or oil in the coolant?

 

[keifer1122]

check fuel pressure,may idle fine but when u hit the gas it dies. if its low replace fuel pump.

 

[Ridgecrest]

The high pressure pump is in the tank and the low pressure pump is on the frame rail if the yours is like my 86 injected model, are your catylitic converters getting hot and swelling, just curious.....good luck with it

 

[nate12346]

When I had the 2.9L in mine. It would get hot quick climbing the mountain roads to the the trails. If it got too hot it would stall and wouldn't start until it cooled down enough. Cracked heads and leaked oil like a sivv. It was a mess.

I would do all of the above posts and pressure test the cylinders if you can.

 

[88Bronco2EB]

Could be a bad O2 sensor, I have an 88 2.9L that had the same issue and it was the O2 sensor. would run great cold but when it warmed up the RMP's would fluctuate until it died. When you first start the engine its at a preset fuel mixture set by the computer, the O2 sensor doesn't kick in until the engine is warm enough. My truck was getting to much fuel and dieing when I let it idle to long.

 

[bronco_lou]

The high pressure pump is in the tank and the low pressure pump is on the frame rail if the yours is like my 86 injected model, are your catylitic converters getting hot and swelling, just curious.....good luck with it

Why would a high pressure pump feed a low pressure pump? I think the low pressure is in the tank and high on the frame rail.

 

[master hec0]

Could be a bad O2 sensor, I have an 88 2.9L that had the same issue and it was the O2 sensor. would run great cold but when it warmed up the RMP's would fluctuate until it died. When you first start the engine its at a preset fuel mixture set by the computer, the O2 sensor doesn't kick in until the engine is warm enough. My truck was getting to much fuel and dieing when I let it idle to long.

i would second that because mine did the same thing and i replaced almost everything before the o2

 

[adsm08]

Why would a high pressure pump feed a low pressure pump? I think the low pressure is in the tank and high on the frame rail.

You are correct sir! The lift pump is in the tank and the HP pump is on the inside of the frame rail almost right under the driver's door.

Also, sounds like O2 sensor issue. If the IAC is new, then your O2 sensor is 95% sure to be the problem. My engine will run almost perfectly with everything but the O2 and MAP unplugged, as soon as that O2 goes out, no dice.