2002 Tacoma 3.4 won't start - and no error codes

Hi guys,

I'm not much of a mechanic but I can do a little.

My truck has 202k on it, and I've put the last 75k or so in my 6 years of ownership. I had noticed every once in a great while the engine would stumble a little on the highway. It only happened maybe once or twice a year at first. That was just a minor annoyance for about the first 3 or 4 years.

It then started to become more frequent, and eventually would die completely, but start right back up. Later on it would not restart and had to cool off. Finally with some help, the error codes were all over the place with fuel, misfires, system too lean on bank 1 and my mechanic friend did some research and said if the it's the ignition module, it can cause all kinds of codes.

I happened to be in town one day when it happened, so I took into the local dealer. They did a full inspection and diagnosis but found nothing wrong, and of course it ran fine. They suggested several maintenance items (surprise, I know), and I had them do everything, except tires. I figured if I do end up selling it, it will be nice to have all factory items recently completed, and if I keep it, I'll reap the benefits. They did full tune up, replaced timing belt, and all the fluids except auto tranny, which didn't need it.

Then is when it ran fine again for about 6 months or so, before it completely failed to run (although it does fire and try to run). So I got the part coming from the parts store. We were both surprised at the $550 cost for sure. But the parts store found some for $350, so I opted for the generic equivalent. The truck ran fine for about the next year, although the occasional stumble gremlin started showing itself again, sometimes tripping the check engine light again. But it continued to run and not die, or start right back up, but again with it tripping the light as often as not. I finally got a code standard and keeping in the glove box so I could reset it.

I talked to the mechanic again and he asked what the code was, so I told him (I think it P1701 if I recall). He looked it up and told me to try cleaning the MAF sensor. So I did some research and cleaned it and wha-la, the light stayed out! I was very happy that was fixed... or so I thought.

The stumble returned and re-cleaning the MAF sensor would work the first few times, for shorter and shorter times, but then died completely and has not started since. I thought well maybe the MAF sensor is actually bad, so I replaced that, to no avail.

I tried lifting a batter cable (for 30-45 minutes) to reset the brain, no joy. I checked for error codes, no errors stored nor pending... ugh. My mechanic friend said it might be the crankshaft or camshaft sensor. But I don't know where those are, nor if they can be checked.

I'm also wondering if the ignition module can be checked (although my friend doubts if that's bad). And ideas?

Thanks in advance.

 

3-1/2 shop days later, my truck is back on the road, running like her old self. It turns out I had an after-market chip kit that went bad. The mechanic found it behind the glove box, removed it, plugged everything back to factory and it started right up. Go figure!