Testing fuel injectors? How?

Hey guys. My mechanic says I've got a bad injector, but wants to charge me an additional 300.00 pull the plenum off my 94 Grand prix with a 3100 to find out. I can get the plenum off myself with no trouble, but how does one go about testing the fuel injectors? I put a long screw driver on each injector while the car is running, and left the tick-tick-tick that each injector makes .. one is slightly less .. powerful than the rest, but I'm not sure if that is a clear indication of an injector failure or not .. help!

Reply to
clevere
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One is the Ohm test. Unplug a wire from the injector and touch the terminals with the ohm meter leads. I don't think it matters which leads touch which terminal

I think mine tested out around 14 to 16 Ohms last month. Take two readings, one with the engine Cold then Hot.

I'm not sure what a Bad ( Ohm ) reading would be. Maybe someone else can chime in here.

I don't know of any other test methods.

I replaced 2 tires & a crank sensor today.

Good Luck

========= Harryface =========

1991 Pontiac Bonneville LE 3800 V6 ( C ), Black/Slate Grey _~_~_~283,907 miles_~_~_

~_~_~_~_U.S.A._~_~_~_~_~_

~~~The Former Fleet ~~~

89 Cavalier Z 24 convertible 78 Holiday 88 coupe 68 LeSabre convertible 73 Impala sedan
Reply to
Harry Face

Harry Face said

I s'ppose you could also check for shorts to ground. Both leads should be opens when measured from lead to chassis.

hth

Reply to
none

Not sure mortal man has the equipment to properly check an injector. I thought they should be around 12 ohms but that's only one check. They can have the right resistance buy still be partially clogged. How much do you trust your mechanic? If you want to DYI, I solved a misfire problem in a 98 Montana by installing a set of reconditioned injectors from

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There's a bunch of places selling recond. injectors but I read of this outfit on another board. Not sure of cost for the 3.1 but it was around $150 +/- for the 98.

Reply to
DonW

Reply to
Geoff Welsh

The problem is that I don't have the funds to replace all the injectors at once. For 6 @ 70.00 (for new) That's almost 500.00 :( I don't plan on having the car much longer.

Reply to
clevere

Hmm ... seems really cheap for an injector at that place ... How long have you had those injectors?

Reply to
clevere

Replaced them in Jan 04 & about 6000 miles ago.

Reply to
DonW

but your going to pay 300 to have them looked at? then replaced if nessacery?

Reply to
M.C. Tee

Your mechanic may be right but if you want to try a cheaper solution, here is one. Get a good fuel injector cleaner, I use Marvel Mystery Oil. Get on the interstate & run it out. Try to keep an average speed of 70-80 mph. Run at least 100 mi. That may take 1 hour 15-20 min but you should see some improvement if the injector is only clogged. If that is the problem all of the injectors should need cleaning.

Reply to
Micah

Reply to
Jimmie

A short (0 Ohm) is a guarantee the injector doesn't work. Resistance within spec is no guarantee the injector works. Since your injector does something I would expect all values to be within spec.

Most likely the faulty injector (if there really is one) is worn out, I recently tried to find a place to check my injector and didn't find anything useful.

Reply to
Simon

Not to pick a nit but that's just over 400 dollars (420). I'm sure your point still stands on that anyway though.

Reply to
SgtSilicon

Thanks Harry, I'll try it. It's a little hard on the 3100 to check hot, but I'll see if I can get into the harness and check there... after I put the fuel tank back in my van

Reply to
clevere

Already paid 250 to have my 'miss' looked at ...

Reply to
clevere

Been there .. done that :)

Reply to
clevere

hehe .. 420.00 plus gaskets, bandaids, and money for the cuss jar = $500.00

Reply to
clevere

Thanks Don. I'm gonna give em a whirl if they reply to my email.

Reply to
clevere

Using that stuff as we speak. We'll see what the mystery stuff will do.

Reply to
clevere

If someone charged you that:

Then told you it was an injector. With all due respect, you were "BUNGHOLED!"

Refinish King

PS What ever happened to customer, not servicing the customer?

Reply to
Refinish King

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