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Valentine One Radar Detector

dom
11-26-2010, 11:43 AM
I see so many of them out there.

Should I use fuel injector cleaner?

How the heck does my mechanic know my injectors are dirty?

Does he have to physically remove them to know?

Do injectors get dirty?

How would my car act if they were dirty?

MikeHalloran
11-26-2010, 01:56 PM
When EFI was new, injector clogging from varnish was epidemic. Stuff that literally looks like and acts like varnish would precipitate from gasoline in an engine left to cool down after it got good and hot. It clogged injector nozzles so they didn't make the required fine spray, but instead shot out an erratic stream, or nothing. The engine mfgrs never anticipated it, and in fact never saw it, because in all of their emissions-over-a-lifetime testing, they never shut the engines off and let them 'hot soak'. Now, they do.

The effect on driveability was distinct, but subtle; at idle or WOT, the engine ran fine. But at near-closed throttle, just gently keeping up with traffic, the engine would act like it was either on, or off. On a carbureted car, you get exactly the same effect from clogged transition jets.

The solution for EFI or carbureted cars is the same; Marvel Mystery Oil. A pint or so to start cleaning, and about 4 ounces per 12 gallons of gas thereafter to keep things clean. I have _never_ had any other additive I've tried make such a dramatic difference, and so quickly. MMO usually cleans things up, as if you've just had a valve job, within ten miles.

Because of the varnish fiasco, mfgrs now do hot-soak testing, and injectors made in the last ten years are much more resistant to varnish clogging, and gasoline formulas have changed, so if you drive a new-ish car, you may never see the problem. Older cars may still benefit from MMO.

I have found _NO_ additive other than MMO that made _any_ detectable difference in my cars.

dBrong
11-26-2010, 02:57 PM
I see so many of them out there.

Should I use fuel injector cleaner?

.... How would my car act if they were dirty?

I have never used fuel addatives... except....

I have found in older cars (6+ yrs) that they do help driveablity issues. These are the problems where a 'tune-up' doesn't really fix.

I have used Sea Foam, and TechTron (sp ?) and they both have helped for idle and just off idle acceleration, and smoothness.

Also the gas gauge stopped working in my daughters 2005 Taurus. A couple of treatments with Sea Foam got it working again. Ford claims "deposits" can damage the gauge. Deposits in the fuel tank????

I suspect injectors, throttle body, and combustion chamber can be marginally cleaned with such products.

IMO, if you have an older car with such problems, give them a try for 2 - 3 tankfuls!

Mustang_Boy
11-26-2010, 10:28 PM
For what it's worth..... the owners manual in my '06 Mustang forbids the use of fuel injector cleaner and additives with the 4.6 V8.

dom
11-27-2010, 06:35 AM
For what it's worth..... the owners manual in my '06 Mustang forbids the use of fuel injector cleaner and additives with the 4.6 V8.

Something to do with the finish on the valves?

MikeHalloran
11-27-2010, 04:28 PM
It probably has much more to do with the rubber parts in the fuel system, which have to be selected to resist all the nasty stuff that's normally in gasoline, plus now, quite a bit of ethanol, which further limits the choice of materials. Apparently at least one part that resists gasoline and ethanol cannot resist attack by the stuff typically used in fuel injector cleaners.