01 Isuzu Rodeo CEL flash on acceleration

02-01-2010, 06:26 PM
Recently (as in today) I had my 01 Isuzu Rodeo LS (3.2, V6, 166,000 miles) serviced for flashing CEL, rough idle and stalling. I was told there was a vacuum leak and that the intake manifold gasket needed to be replaced. I asked them to replace the plugs too since I had never had them replaced in the 4 years I have had it. (I know bad me!!) I picked the truck up today, started it up and it purrs like a kitten but the engine light started coming on during acceleration. Anything under 1.5rpm, no light. Anything over that, flashing CEL. Took to AZ and code is for multiple misfire P0300...

Now from what I have read on the postings, I need to find out what kind of plugs were put in. Looks like the 00+ Rodeos are really picky and want Denso platinum plugs (K16PR-P11) and that it will keep flashing if anything but those plugs are in. Also saw a mention of the ION module, thoughts? My concern is that I saw that the flashing light can indicate possible damage to the catalytic converter...

Can someone help a girl out? LOL, I am learning way too much about my truck that I could turn a wrench on the side

02-01-2010, 09:34 PM
You are correct; check with the shop to see what type of plugs they put in.

Plugs in these trucks are typically good for 75k.

02-03-2010, 08:04 AM
The shop called me yesterday and I asked about the plugs. They told me they used regular plugs and what was spec for the truck. I looked in the owners manual and there are 3 different plug types, one of which I think is the Denso plug. Now here comes the girl question... It's a V6, so 1 plug per cylinder right? 6 plugs?? The shop will install my plugs but said none of the local parts places have them. I am going to search online tonight.

02-16-2010, 07:33 AM
I guess you've probably got it straightened out by now, but my experience with the very same vehicle is that the plugs don't really make a lot of difference. My '01 Passport came from the factory with Champion RC10PYP4 plugs and it always ran just fine - no knocking on reglar gas. It did set P0300 random misfire codes in the computer (without activating the CEL) from the day I bought it new, so at 40K mi I installed K16PR-P11's thinking that might eliminate the P0300 codes. It ran just the same as before - fine. And it still set random P0300 codes. I just ignored them & its run just fine since.

Also had the flashing CEL at above idle starting at about 90k mi. On mine, that turned out to be a faulty drive-by-wire module on the throttle body. I took the white cover off the black plastic TB accellerator circuit module (on left side of the TB as you face the engine, where wiring harness plugs into the black plastic part) and very carefully cleaned that up inside with electrical contact cleaner, and that stopped the flashing CEL for about a year. It finally came back & I had to replace the entire throttle body accellerator circuit unit (the black plastic part). That stopped the flashing CEL. Cost about $85 for a new one as I recall.

02-16-2010, 01:25 PM
Actually I haven't gotten it straight yet! We got hit with alot of snow, so it sat for a couple days. It's still running sweet. I did order the plugs and had them sent to the shop. The dealer/shop were quoting me $23.52 A PLUG!!! I got them for $6.89. Problem is the place is only open Monday-Friday, when I am at work!!! So I am trying to figure out what next.

Thanks for your little tidbit. Someone told me to disconnect the battery and that will reset the code. But given my luck, I am sure it will be back on in no time!

2001 Isuzu Rodeo LS 2WD

02-16-2010, 10:58 PM
This problem, with the 2nd generation rodeos, is so common I can't believe somebody hasn't figured out the cure yet. I've read claims that the problem is caused by everything from - intake manifold gasket, injector O-rings, fuel pumps, EGR valves, bad gas, wrong spark plugs, Idle control valve (which I don't think it has), throttle position sensor, MAF sensor, fuel pressure regulator, throttle position sensor, weak alternator, etc, etc.

I finally just cleared out the code and make sure I let it warm up for about a minute from cold start. I hate that but I can't afford to keep throwing parts at it.

02-26-2010, 02:08 PM
Clearing out the code is great temporarily but does not correct the issue. I took my truck back to the original repair place today and they said since it was running fine, they wouldn't do anything. So I got my plugs and left. I did have them put in and it took the constant light off, and stayed off for about a 1/2 hour, which is good but I still have the flash on acceleration above 1500rpm... Running fine otherwise... Not sure if it might be oxygen sensor, egr, fuel injectors.... Grrrr

02-26-2010, 09:23 PM
Isuzu Tech for 10 yrs now. No I dont know everything. 200- Rodeos may operate fine with some A/M plugs (for a while) Isuzu used to use Champion plugs untill they realized they are no good for the 3.2 with the Ion module. Nippendenso plugs should be used if not you at some point will get missfire DTC's even if you do not feel it. Someone posted something about the common problems yes you are correct, however only one of these is an Isuzu problem all of the rest is the genuine GM (government Motors) garbage parts. 90% of parts replaced on these are from my experience GM parts(fuel pump, egr, pcm, wiring, transmission) there are many others too many to list. Guess what I am trying to say is ty GM for messing up a good vehicle. Oh and the stupid little 4 cyl engine used in Rodeos (Holden industries Austrailian division of GM) the engine GM was so proud of they didnt even use in their own vehicles. I really have a hatred for GM.

02-26-2010, 09:26 PM
furgo if it is still flashing after the correct plugs have been installed I am sure it is safe to say you need an Ion module. Before replacing it post all DTCS for me.

02-26-2010, 10:20 PM
It's P0300 multiple misfire. Thanks

03-01-2010, 06:11 AM
Alright guys... 2 more questions! And btw, thanks for all the input. I went and bought a repair manual & little scanner to help. Can the coils cause the flashing CEL if #6 is not in the correct location? I'm thinking I need to have the coils checked, since the guys at the first shop "weren't aware" of the 0+ Isuzu being sensitive to plugs. And where in the heck is the ION module? Don't see it in my book. Is it under the black cover? I know it has 3 connectors.

Sorry for all the questions, just trying to make sure I keep this thing running properly for the next year or so! Thanks again

03-02-2010, 09:21 PM
yes you can get a miss-fire if coil #6 is in the wrong place.

i think the coils have a part number on them.

03-02-2010, 09:48 PM
Thanks Amigo! Just trying to figure this out without paying an arm & a leg... I had a flashing CEL today on acceleration from work to picking my daughter up. When I started truck up after that, the light was constant - so that has me wondering now. Someone mentioned another way to figure out CEL is to turn ignition on and off four times fast and count how many times it flashes before and after pause. (ie 2 flashes, pause, 3 flashes = 23) I don't know how accurate that is but at this point anything is game. I do know that I have a crack in the evap canister and will need to replace but could this also cause the flashing CEL and P0300?

Cat Fuzz
03-03-2010, 11:36 AM
A flashing CEL means there is a catalyst damaging misfire. Meaning, you could destroy your catalytic converter by driving it like that. Counting flashes does not work with OBD2. You must have some kind of code reader. Cheap code readers can be bought at Harbor Freight for about $55. They only give you the codes and you have to look up the definitions. More expensive tools will give you the definition on the screen.

A crack in the evap canister will cause a CEL but not a flashing CEL.

03-03-2010, 09:55 PM
This tip is regarding a Trooper but the symptoms sound identical . . .

03-05-2010, 07:38 PM
Thanks I saw that and didn't really think anything of it at first glance. I did hook it up to my scanner and got this (gibberish to me): P0300 (of course!), MIL ON, MONITORS, 2 Inc(omplete) - Catalyst, Evap. 6 Ready - Misfire, Fuel, Comp, 02 Sensor, 02 Htr, EGR. I noticed when I start in the morning that is revs up and down a few times on it's own. CEL flashes on acceleration when cold, sometimes will come on for a little and then it goes out completely. It's done that for 2 days straight.

03-05-2010, 08:21 PM
Just because you have a misfire code (P0300) doesn't mean you have an ignition problem. I once had a P0300 and it turned out to be the fuel pressure regulator. Have you checked your fuel pressure?

03-08-2010, 06:42 PM
Ok hopefully this is the end of this issue. I took my truck to have the oil changed, engine cleaning treatment with a performance coating and fuel injector cleaning service. And the darn light is off! Thanks to all for answering my gazillion questions

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