1987 2.9 owner worried about possible cracked heads!

[chris1]

I bought a 1987 2.9 ranger about two yrs. ago and have been driving it without any problems until the past few months. Started noticing lack of power and raw smeeling emissions coming from the tailpipe. Code tester points to the EGR system but I found a loose distributor. Reset the timing but it doesn't always idol smooth. EGR is clean and appears to be working. doesn't appear to have vacuum leaks. I just replaced the o-sensor. I worry about either a stopped up cat pushing emissions back up the line or after reading about how common the 2.9 is for cracked heads in the early models in the tech library on this site I'm afraid of that as well.. Any suggestions? I don't see oil in my coolant as I just changed it out yesterday or coolant in my oil which was changed last weekend. That's a positive sign but the smoke bothers me. Maybe a compression check?

 

[AllanD]

The usual failure on 2.9 heads is an internal crack that releases coolant into the crank case.

Any other type of failure is avbout as likely as you winning the lottery.

I'd look for a management system issue because the symptoms you
are describing cannot be attributed to the lube oil becomming
contaminated with coolant.


on an '87 I'd be looking at the condition (integrity) of the vacuum lines
that control the EGR system.

 

[chris1]

Thanks for the advise. I'll recheck everything and post back!

 

[chris1]

To ease my mind I ran a compression check and all was ok. On to other things. Thanks for the info.

 

[chris1]

Since at this point I have replaced the Vacuum control for the EGR vale and the sensor that mounts just above it as well and the O-sensor. What about the MAP sensor? Or the AIC? These are the only thing left I can think of that might be related to the problem I'm having. Strong emisson smell coming from the tailpipe. Runs good except for a dipping idol at stand still.

 

[lzarnch]

cracked heads

if your heads are cracked i have the world replacement heads fully assembled i am willing to sell, i found some performance heads and dont need them any more. they cost $325 ea + shipping from summit racing but i will sell for $300 ea. they are brand new never used, i just primered them so they wont rust

 

[Navyman]

what to check as a suggestion

Possibly one of the grounds good be bad. As a suggestion you might want to check that. Another source could be a kink in the Wire to the Injectors.

Good luck. Navyman

 

[almostclueless]

There is smoke from the tailpipe? Black smoke by chance?

If the compression checked good and the oil isn't milky white, yet there is a raw gas smell, black smoke, and loss of power, I would be looking at replacing the fuel pressure regulator and the spark plugs afterward.


There is the outside chance it could be ignition, too.


Dont let the cracking heads scare you....it doesnt always happen.


Don't put off fixing this and good luck.

 

[chris1]

Thanks for the advice. I will check the grounds. Never thought of that but yes having a bad ground can cause all kinds of wierd things. I've seen that before. I'll also recheck all wiring.

 

[chris1]

The power is great. The fumes and grey smoke which has to be because of the rich burn is my problem. The fuel pressure regulator is loud and makes a clicking or buzz sound. Seemed loud to me? Something I found to be odd was when I took the rubber intake tube loose from the throttle body and the air filter housing for easier access to replacing a thermostat last Thursday, I noticed engine oil in the lower inside of the tube? I had just replaced the PCV valve and the EGR valve last week and the PCV valve rattled from the moment I put it in. Rather loudly. Don't remember one doing this before. Wondered at first if this might be the reason for my smoke as it seemed to be sucking oil into the intake. Why would this be? Poor engine ventilation? Or bad new PVC? I took it out and put the old one back in. Still had some smoke and still had the fumes but why would oil be coming into the throttle body? Clearly looked to be coming in via the new PCV valve. I'll drive it for a while with the old one installed then recheck the intake. Last resort was to disconnect the O-sensor. I saw a post that offered that as a temp. remedy to see what would happen. The smoke stopped but the fumes remain. The idol was better also. Still wondering about the Cat? Hard to tell at the moment how much pressure is really coming from the exhaust to see if the Cat might be plugged because it needs replaced.