Mechanics

QUESTION HESITATIONS, SLUGGISH ON ACCELERAT

2001 Isuzu Rodeo

Shakes or Wobbles problem
2001 Isuzu Rodeo Question 4 cyl Two Wheel Drive Automatic 130000 miles

The car hesitates, gets sluggish, will jerk from getting power back and loosing it again on acceleration. Intermitent. I have a code for p0300 multiple cylinder misfire.

This is what I have done:

1. Had code for p0303 changed all plugs (Bosh) got better for a few weeks, now it is doing it again. Ckecked cables by unpluging and checking for obvious misfire. Cables seem ok

2. Had a code for bad cam sensor - Replaced it code gone, still have problem.

3. Had transmission fluid low code - had filter and fluid changed at Mr. Transmission fuel filter too- code gone.

Did some research online and came up with following
4. Bad gas(did 2 treatments of gas treatment 1 (stabi)l 1 specific water treatment);

5. Cracked head or head gasket, but no evidence of water when changed plugs.

6. Reference to only using spacfic OEM (Denso Plugs).
Haven't done this yet.

7. Ran into a guys account with same problem and his ended up jumped timing. So, I was thinking about changing the water pump and belt and setting time this weekend as 130000 needs to be done I think anyway. Haven't done this yet either, but if it is this the belt breaking could cause major problems. Does it fit with the code?

The only code I have now is p0300 multiple cylinder misfire.
Avatar
Saildbl
April 2, 2009.




Well it does fit the code if the belt jumped. But either way if the belt has not been done at all then it is more then time to do this anyway. It should be done about every 80000 miles anyhow. Now with that said there is other things that can cause a multipul missfire. Like the TPS or the coolant temp sensor or coil breaking down or ignition module and so on. So I would change the belt anyway if it has never been done and then clear codes and see if it running as it should and then if not lets start with a coolant temp sensor test and TPS test. Now the coolant temp sensor test is very simple just unplug it and use a digital multi meter and set it on ohms setting and ohm the sensor (not the wire harness) and do this cold so that you can give me the reading and the temp at the time you do the test. Let me know what you find and we will go from there.

Racefan966
Apr 4, 2009.
Changed belt and water pump. Cleared. Still have problem. Coded p0303 this time. Which is what I had before I changed plugs.

If you can tell me where the coolent sensor is I can check it now, otherwise, I left my haynes manual at my fathers house, and can look it up after I go get it in a few days.

Tiny
Saildbl
Apr 7, 2009.
It is at the rear of the engine in the intake manifold near the EGR valve. Here is a pic to help. Now if you ohm it (not the harness) and do this when it is cold and get back to me with the readings and the temp at time I will look it up to see if it is in spec.


http://www.2carpros.com/forum/automotive_pictures/249564_Graphic_65.jpg


Racefan966
Apr 7, 2009.
Put in Denso OE plugs ran fine till I got on the interstate. Still seams better, but it did that intermittently before.

Took off that coolant sensor, was not easy. I had a lot of trouble getting the volt meter in there, had to go mostly by feel, but I got a reading of 4.53 at 20k. The car has not been started in over 30 hrs. Temp outside is 64.

Tiny
Saildbl
Apr 12, 2009.
Well it is out of range it should be couple of thousand less then it is. I would replace it and see how it does. Let me know how it goes.

Racefan966
Apr 13, 2009.
It is kind of hard to get back there and see what is going on. Any info on the easiest way to get it out and the new one in? It will probably be this weekend before I can do it.
AD

Tiny
Saildbl
Apr 14, 2009.
It might help to get an EGR valve gasket and remove it to gain better access to the coolant temp sensor. That is all I can think of to help make it easier. You have the car so you will have to look to see if that will actually help. Let me know it goes and we will take it from there.

Racefan966
Apr 14, 2009.
Replaced the coolant temp sensor yesterday. It was actually easier than getting the ohm reading. Truck seems to be behaving better, but still getting jerk and hesitation intermitently this morning. Engine light back on but havn't coded it yet.

I had noticed that from time to time the fan would run/cycle after I stopped. I havn't heard it do that in a while, thought new sensor might get that going again. Hasn't yet. The other one seemed to have needed replacement.

I read though my description and noticed that I hadn't mentioned that it has a knock for the first quarter mile or so. Not sure if that is helpful and the key is stuck in the ignition.

Should I give it a little more time as I have driven it twice since changing the sensor or check something else?

Tiny
Saildbl
Apr 23, 2009.
The fan is cycling again. That's good. The truck is still intermitently jerky and sluggish. Should I check the TPS next? If so, do I take an ohm reading and which prongs it has three?
Thanks for your help.

Tiny
Saildbl
Apr 29, 2009.

AD