Roark

1989 3vze with ~165,000 miles..

After she sits for a few days, especially in the winter, it takes a solid 4-5 seconds to crank, at best. Normally, it'll take 2-3 long cranks to start.

I went out, OHM'd the injector terminals and it read consistently 6.0-8.0Ω. Took the injector out, cleaned the injector itself, re-OHM'd it, and it then read about 4.9-5.0Ω.

FSM calls for reading of 2-4 Ω

NOW. My question is:

If the injector is defective, will it read ABOVE the suggested output? Upon cleaning, it dipped down to the recommended reading, but still stayed above the suggested. Assuming I measured the injector properly (meter on 20Ω/lowest Ω setting), does this call for a new injector?

Also, I cranked the engine with the injector inside a container, and it DID spray some gasoline. However, I can't determine or describe the amount of fluid as anything more than "some".

Roark

Buuuuump

scope103

Your resistance measurement is as close as you are going to get; unless you have a very expensive meter with a 4-wire "Kelvin" connection, accurately measuring resistance below 5 ohms is very difficult (the resistance of your leads alone is probably close to one ohm).

The CSI is on only while you're cranking; it's not designed to put in a lot of fuel. If you were able to get it to spray while cranking, that's the most reliable test you can do. http://personal.utulsa.edu/~nathan-b...29coldstar.pdf

You might look at the ECT sensor. http://personal.utulsa.edu/~nathan-b...40engineco.pdf It determines the base mixture based on temperature, and if it is reading "high" you may be too lean to start, even with the help of the CSI.

Roark

Thank you for the insightful respond, scope. I'll be sure to check the ECT ASAP as possible.

An aside: I turned the key and left it in the on without cranking for ~10 seconds, and I cranked and it fired in just a second or two. This leads me to believe my fuel pump may be losing some of its strength, as well. ..for another day!

scope103

Ah! That can be checked directly.

There is a check valve in the pump, to hold pressure in the rail when the pump stops. If the valve starts to leak, each time you start you have to bring up the rail pressure, and that can lead to a small delay.

You can force the pump to run with key-on and a jumper between FP and B+ in the diagnostic connector. You should also be able to hear the fuel LEAVING the fuel pressure regulator (to return to the fuel tank) once the rail gets up to pressure. So let your rig sit for a few days, do the jumper thing, then pull the jumper out and try to start it within a short bit. If it starts right up, that points to a weak check valve in the pump (you can't replace it separately, replace the pump. $30-$150 at RockAuto; replace the strainer at the same time)

Roark

I'll let the truck sit until Thursday or Friday and then check the fuel pump as per your instructions.. thank you!

And if you're still listening, I've attempted to check the ECT 3 times now, and each time it hasn't even registered a reading! When I remove the connector, the engine will NOT start, but with it plugged in, it will, so I'm sure the sensor itself works. For reference, I'm pulling a green connector that corresponds in location to the one in your link. I just CAN'T get a reading with my ohmmeter. I've tried red/black and black/red under all different Ω levels. I even shaved some of the plastic grips from the leads so they'd both fit into the sensor. I know the meter works because it shows the same output of the truck's battery as my other ohmmeter. What am I doing wrong?



Not my pic, but I'm checking the sensor with the dark orange/red arrow.

scope103

Nope, not possible. You can get zero ohms, or infinite ohms, or something in between. But there ain't no such thing as "hasn't even registered a reading" on a resistance scale.

When you touch the meter leads together do you get zero ohms (or something less than 5 ohms)? When you hold them apart does it indicate infinite (or over-range)? Just for laughs, what do you THINK the resistance should be?

Yes. Two-wire connector, with the gray housing.