89 ranger 2.9 problems

[saling4]

History: 1989 Ranger 2.9 xlt ext cab 190K miles

running great until it Overheated and cracked a head (Broke a heater hose on freeway).

Okay so I tore it down put new gaskets and heads new vacuum hoses, etc.

Back together and running fine just a little rough, but drivable.

After about 10 miles it starts overheating (new radiator and thermostat, radiator cap).

Pull out thermostat and it is not opening. Drove it without TS for about 100 miles. Ran fine just didn't seem to have the power it used to.

All of a sudden it gets real loud and check engine light comes on intermittently.

Replaced TS with a new 180*,

Pull it in garage and check timing first....Wowsa, I had it set at about 10* ATDC. Reset to 10*BTDC. No change in running smoothly...still loud as heck. Found big hole in muffler so now I know why it got loud.

Pulled codes and the only ones were KOEO 29, 41. Didn't worry about the 29, but the 41 leads to the O2 sensor.

Pulled O2 sensor and did the bench test with a torch. Heat up and it goes to .9 take heat away it drops to Mv's quickly. Hmm, seems good.

Put O2 sensor back in and connect meter. Start truck and it goes to .8 to .85 volts and stays there. Pull vacuum hose and idle increases, but voltage doesn't change or goes up (I thought it should go down).

After running for 20 min's I found that the radiator water is still cold.

Checked for codes and there are none.

So I guess my question is what now?

This time I will check whatever you gentleman suggest and post results until I get this solved. So this may go on for awhile.

 

[dieselboy740]

how's your cat?

 

[saling4]

Its in 1 piece, but that is all I know. Is there a way to check it?

 

[dieselboy740]

you said it's loosing power? And over heating still? Shake your exhaust there shouldn't be any rattle from the cat. Or pull the flange and lookinside of it. What kind of loud like lifters? Exhaust leaks? Or intake noise if it's exhaust leaks and intake noise I'd say cat could be plugged.

 

[saling4]

Since I took the TS out it is not overheating. I put in a new 180* TS and now the radiator is staying cold. Gauge is moving up just to the C on the gauge.

I found that the reason it go so load was a big hole appeared in the muffler. If shaking the CAT will tell me if it is good or bad I will do that.

Another clue maybe is that with the car in the garage I can see that it is spitting out black stuff out of the exhaust.

 

[cocoasranger]

Check that the thermostat is not in backwards. Also, you can put it in a pot of water and heat it till the water boils; the stat should start opening before it reaches a rolling boil if it's good and fully open at a rolling boil.

Shaking a cat only tells if there is mechanical damage inside. To test for blockage you can 1) substitute a test pipe for a short run, 2) run the engine at a brisk rpm for about 5 minutes while stationary; if plugged the cat usually will glow red, 0r 3) separate the exhaust just before the cat and take a short drive to see if power increases.

Usually a plugged cat will let the car idle fine and drive ok under light throttle; the more you hit the gas, the more the problem escalates.

 

[Zachalanche]

are you still at a power loss after setting the timing correctly? also are you still getting black exhaust since this timing change?

 

[Tedybear]

This might sound silly, but check the o2 sensor wiring. Ours managed (with a little help from the last owner) to short out against the exhaust itself, melted through...and due to it being a "Heated" o2 sensor? I had to replace about 15 wires for about 1' where the wiring burnt together.

I'm also not sold quite on the "flame" test for the O2 sensor. Keep in mind the O2 sensor detects the presence of Oxygen in the exhaust. The sensor is 'heated' in order to get the detection part up to temp quickly, however it's still measuring the oxygen content of the exhaust. (I might also be mistaken LOL! Just trying to wrap my mind around the test you did) Also to note, the computer will IGNORE the O2 sensor until it reaches "Closed Loop" operation. Meaning the system will work with basic inputs (map sensor, TPS, temp sensor) to regulate off a preset air/fuel set...until it's warmed up enough to start fine-tuning things.

If you are getting an O2 error? It might just be enough to say heck with it and just replace it. (they are recommended to be replaced about every 60,000 anyway..according to the interval recommended by the parts house I deal with)

The black stuff coming out the exhaust is carbon buildup...(don't let Al Gore see ya!!) It's normal to get a little bit of black smoke when first started up if cold. The engine needs a bit more 'rich' air/fuel mixture while cold/warming up. But if it's really spitting out black crap? She's running way to rich, and the O2 sensor can create this. (eg: The O2 sensor reports back "exhaust to lean" to the computer..Perhaps not quite enough to trigger a C.E.L....but enough for the computer to fire the injectors more for the duty cycle--the result would be running rich)

I'll keep an eye on this one. It's interesting.

S-

 

[saling4]

I haven't taken it out of the garage for a power check since it is running rough...but I will. If I can attach a pic I will show what was going on when I first put it in the garage. I don't see how to attach a pic. I will say that with a plain piece of white paper I have very little black soot at this time (since resetting timing).

Which reminds me that the power loss reminded me of a "governed" vehicle. You can feel that there is more power, but it just won't go. The power band would max out around 3000 rpm. It would drive fine on the freeway (speed wise), but 3000 was about maxed.

 

[saling4]

I am not "sold" on the flame test and since it checks bad in the vehicle then I am even less sold. However, Since the radiator never warms up (after 20 min's still cold) I am not sure I am getting a true reading. On top of that the O2 Sensor is 190K old, but I have read that they should "never" really go bad...SURE I BUY THAT.

Old thermostat it overheated....No TS it ran cool (per gauge) but hoses and radiator warmed up.....Put in new TS (180*) and now doesn't appear to warm up.

 

[spaz1879]

i have the same kind of problem and my truck has around the same mileage and is a 88 and my o2 sensor was all messed up so i just took it off and drove without it so maybe i could be your o2 sensor? or is your crazy heating of the o2 sensor fool proof? just thought i would chime in