OT: General Opinions (?)

That's it. Flat rate mechanics don't get paid well (or at all) for diagnostic time. They get paid to replace parts. The faster they can replace parts, the more bucks they make. Which means a young, inexperienced kid can Easter Egg (or Shotgun) a problem and make more money than an older, wiser mechanic who spends the time to fix the damn thing the first time can. Sad.

-Carl

Reply to
Carl Byrns
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So there are. They don't mention them in the text of the manual, but a close inspection of the cross-section diagram shows them to be there. There is no discussion of cleaning or inspectiong them, either.

I would think if there were a particulate thing going on inside the injector rail, the techron would not help in the least.

Right, but they could possibly be going away gradually, ie, diminishing in width. If that were going on, it would be because the EFI computer might be getting bad information from a sensor somewhere.

BTW I have also checked the plastic tube that connects the mass flow air sensor to the throttle body. It seems to have no holes or cracks.

Jim

================================================== please reply to: JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com ==================================================

Reply to
jim rozen

It is often not particulate matter, but a varnish type deposit which Techron (or many other GOOD injector cleaners) will remove

When the sensors go, they go. They can be intermittent, but they do not fail progressively and then come back instantly when you restart. The integrated ignition does not have the pernicity cam and crank sensors that DIS uses. The 3C does not use a MAF sensor. So, I guess I'm saying injection control is a POSSIBLE cause, but it would be way down the list if I were troubleshooting the system.

I think you mean the Manifold Absolute Pressure sensor (MAP) . Low MAP will cause the engine to run pig rich, so I doubt MAP is your problem, unless it is electrical - and like I said, I don't see the sensor gradually leaning the system and then coming back to perfect on restart. Don't see it being WOT dependent either. On the other hand, fuel flow would be a definite, repeatable, WOT specific failure mode.

I'm still voting for cruddy pre-screens on the injectors. Particularly if running Shell gas, or Petro Canada in Canada. Not sure how the American gas stacks up, but there have been deposit problems making GM and Chrysler fuel guages mis-read up here with those two in particular. Techron supposedly solves the problem over time. If the Camry were mine, or one of my customers' when I was in the business, the injectors would come out and go for an ultrasonic cleaning at the injection/diesel shop. If it doesn't fix the problem, it will help the spray pattern anyway and make the engine run cleaner/smoother at idle/mid range.

Reply to
clare

Thanks. I will keep putting the techron in, but I could imagine that it would be within my capability to remove the injector rail and injectors, and clean them. I have an ultrasonic cleaner.

This was actually one of the scenarios I had considered, and rejected (something between the fuel line at the injector rail, and the injectors themselves, that was plugging up and then relaxing when the fuel pressure/flow dropped.

I've seen several fuel problems that behave that way, a screen or filter will clog when flow rates are high, but the goop drops off once the motor starts, and allows nearly immediate re-start.

I guess I also left out the history of the car - which is that it was my parent's second string car for a long time, and it was not driven much. I would sit in the driveway for months at a time, idle. Hmmm.

Jim

================================================== please reply to: JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com ==================================================

Reply to
jim rozen

Just a thought on cruddy fuel system. I had an '86 Celica GTS that I put

208,000 miles on without ever having the injectors cleaned. It was still running well when some overage bimbo ran me down in the grocery store parking lot. The first few years I ran a can of Tekron every month or so; at the same time I was running regular gas in winter and plus in summer. I later switched to premium when the engine knocked with AC. During this time I had to clean the tar out of the throttle body every few months. I finally switched to Amoco Gold and it stopped the tar completely; I also stopped the Tekron. Considering the price of the addative overall cost probably wasn't much different. The engine also ran better. It might be worth trying a few tanks. YMMV
Reply to
keith bowers

SNIPP

The more I learn about the car, the more convinced I am. Old gas, particularly of questionable quality, and fine screans don't mix.

Reply to
clare

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