Bucking Engine, No Power, Spark Plug Questions

Question ?
I sprayed carb cleaner around my intake gasket and the rpm's did not raise. I tried it 3 times. My Rodeo is running so bad now I really can't drive it. I don't really think the intake gasket is bad now. It idles fine until you try and drive and accelerate. It then bucks like I described until you back off the pedal. It's like the engine is going to cut off when trying to accelerate. Back when I checked my plugs with 45k on them, they had black carbon all over the circle edge of the plug and on the tips, plus the base of the plugs are rusted around the porchelin. Do you think it might be my plugs causing my Rodeo to run bad like I described? I've cleaned the EGR valve and replaced the PCV valve and Fuel Filter. I don't know what else it could be. What other things might be causing my problems? It's got me puzzled.

I know the right plugs are the Denso PK16-PR11's, but has anyone tried the replacement Iriduim Denso IK16 plug. It is supposed to be an exact cross reference to the PK16 plug and has a brighter flash for better power. Some people say it has helped with gas mileage as well. At least this is the info I got when I talked directly with Denso. Has anyone tried these Iriduim plugs in their Rodeo? Were there any problems noticed running these new plugs?

Michael


Previous Thread:
New to Site...
Can anyone help me narrow down a problem I am having with my 2001 Rodeo 3.2L with 46k miles. About a two months ago it was hard to start, I had to pump gas pedal. It happened again about a month ago. Then three days ago the engine shut off when I turned right into a driveway. Then two days ago during acceleration the engine is acting like wants to cut off, bucking during acceleration. If I back off accelerating the engine is fine. It did this bucking thing, like the engine wants to cut off again two days ago. Not to mention, my gas mileage has gotten worse over the last six months. I think it should be better than 12 MPG, even after installing a 2.5" suspension lift with 265/70/R16 BFG All-Terrains and SuperWinch manual locking hubs.

Maintenance I've done recently:
I've read the forums and did a few things suggested, didn't solve problem.

1. Cleaned Throttle Body Plate and hoses. Couldn't find EGR valve.
2. Replaced PCV valve
3. Flushed tranny fluid with Mobil 1 synthetic at 42k
4. Checked plugs at 45k, a little rusted (Denso), gapping is good.
5. Installed K&N airfilter in air box
6. Replaced and repacked front wheel bearings 42k. Blue burn marks on spindles.
7. Replaced surpentine belt at 32k.
8. Running Mobil 1 5W-30 synthetic motor oil w/Mobil 1 oil filter

I am not getting a check engine light. The dealership thinks it is an intake gasket problem. However, they want $85 to diagnose the problem.

Does anyone have any ideas or run into these problems and knows what the problem is? F.Y.I. My vehicle was made in March of 2001.

From what you are describing, I would not suspect the intake manifold gasket. A cracked IMG typically only acts up under high vacuum situations like idle & startup. When you installed your K&N airfilter, did you oil it? if so, some oil may have carried over to the mass airflow sensor (MAF) just downstream of the air filter box. A fouled MAF will cause the concerns you describe & does not always light up the check engine light. Pull out the MAF & CAREFULLY clean it with cotton swabs & electrical contact cleaner. IMHO- K&N air filters dont do much for the 3.2/3.5 anyway. These engines are pretty much maxed out given their small displacement- unless you want to bolt on a supercharger. Same goes with the spark plugs. With the setup the 2000+ 3.2/3.5 has, you really cant enhance the ignition system further on these engines. Stick with the stock plugs.
G/luck!
Joel

if so, some oil may have carried over to the mass airflow sensor (MAF) just downstream of the air filter box. A fouled MAF will cause the concerns you describe & does not always light up the check engine light. Pull out the MAF & CAREFULLY clean it with cotton swabs & electrical contact cleaner.


More good info for the FAQ page! Thanks Joel!

The vacumn sensor for the idle could be your problem. It is located on the throtle body and controls your idle. Mine went south and caused similar problems. My little electric motor only worked when it wanted and that was not often. New was about $40 at the local auto parts store. Took 2 screws and less than a song on the radio to install.

I did use the oil on the K&N filter. I checked my MAF sensor and it was coated with black carbon or grim. I cleaned it and I'm still waiting for my new spark plugs to get here. I hope the dirty MAF sensor was my problem. I just hope that the MAF is not bad now. We will see though. If it is not the MAF, then I am back to square one trying to figure out what's wrong with my rodeo.

Thanks rodeo02 and amigo2-k and everyone else for all the advice and taking the time to help many of us out. You can't get this type of info. anywhere else. The dealership doesn't even know, or at least they won't tell you unless you pay them to diagnose the problems. Thanks again.

Michael

hmm try 2 - 3 bottles of dry gas (water remover) on your next fill up & a injector cleaner i use lucas (white clear bottle) i had the same problem. i ask the user car dealer he hasn't gotten a clue what or how to fix it(95.5 LS rodeo) my dad said to try the gry gass & cleaner for like the next 6 months After like doing this like 3x so far, i then relized why people like the isuzu trucks. i mean when u hit the gas the truck moves!! i didn't relize that some gas stations cut the gas by adding water to the gas. making it cheaper for them to sell it & destroying your engine in the proccess. P.S. ever see any one cutting the gas in any station report them ASAP!!!!

Hey guys, for those of you who have cleaned the MAF, how do you remove it? Is it the metal doohicky seen at the bracket between the air filter and intake tube in this shot: http://www.pureisuzu.com/98-02_rodeo.htm.

Hey guys, for those of you who have cleaned the MAF, how do you remove it? Is it the metal doohicky seen at the bracket between the air filter and intake tube in this shot: http://www.pureisuzu.com/98-02_rodeo.htm.

Just unclamp & unplug from the air tube & CAREFULLY clean the sensor in the center thru the mesh. Use a "Q" tip & electrical contact cleaner. If you are running an aftermarket air filter, cone filter, etc.. the MAF is probably dirty.
G/luck
Joel