94 mazda b2300

[94b2300ranger]

cheap and dirty way to test injectors.

do this outside, with plenty of ventilation!!!!!
remove injector.
obtain constant supply of air, about 65 psi. will need a shutoff valve in the exit line.
using whatever fittings are necessary attach the air hose to the injector, a quick coupler works great.
keep injector upright, pour some gas ,or something safer like rubbing alcohol, into the injector, attach air line and pressurize.
watch for leaks.
hit the connector with very short bursts of 12 volts to spray the gas out.

helpful hint: make the sparks at the remote power source, not at the injector.
keep the air line positioned so the gas won't run downhill back into the hose.
if you use gas, the spray will be very flammable, no "hey Joe, hold my beer" stunts, OK?

I did something like that and everything checked out.


So after testing the injectors, they ohm out between 16.0-.2 across the board, checked for leaks and clogs. They seem fine to me. I was messing with the plug wires on the coil pack and i pulled wire 4 from the pack and then 6, went to pull 5 and it jumped the arc to my finger, but didn't shock me. The spark was orange/light orange.

It starts no problem on cold start, but doesn't start after. So this is what i think. After the cold start, I shut it off and try to start it again but with the weak spark i'm not getting full detonation when trying to start it again and i'm just dumping fuel into the cylinders and compressing it past the rings, which would explain the fuel in the oil and no restart. So I ordered a new coil pack and it will be here Thursday.

Does this sound like it could possibly be my issue? Or am I just losing it trying to find this problem?

As for the high idle issue, I'll tackle that once i figure out the run issue.

 

[pjtoledo]

do you think its a weak coil, or corroded wires preventing the coil from getting full current?

 

[94b2300ranger]

I think it's the coil. I have new plugs and wires.

 

[BlackBII]

Have you tried push starting it when it won't start? I once had an issue getting good spark because the starter was drawing so much power.

Have you checked all the engine/frame grounds to make sure everything is grounded well enough?

 

[94b2300ranger]

Have you tried push starting it when it won't start? I once had an issue getting good spark because the starter was drawing so much power.

Have you checked all the engine/frame grounds to make sure everything is grounded well enough?

I didn't think about push starting it, i'll try it tomorrow after work. I get my coil pack tomorrow, so i'll try it if that doesn't fix it. The thing that gets me, is the no restart right after it was running without any help.

I definitely checked the grounds, I don't know how many times. I build emergency vehicles and 12 volts is what I do.

 

[94b2300ranger]

Since I'm waiting on my coil pack, I decided to install a set of Ridgid back up lights into my bumper. I just mounted them and decided to call it a day. will wire them up tomorrow, as long as the coil fixes my problem.

 

[94b2300ranger]

I tried the bump start and no luck. so im at a loss, coilpack didn't solve my issue. where are all the "experts/technicians" at? surely they have some input or knowledge that can be put forth. I'm looking for the ones who have answers to most problems on the forum. i've seen them post but yet haven't chimed in on my problem. iv'e abused the search function and have come to nothing but dead ends. i do appreciate all the guys trying to help me with this issue up to this point.

 

[BlackBII]

So at this point, the issue is that the truck won't start at all if it's hot/warmed up?

Did you get the idle issue fixed?

 

[86beater]

Ignition control module? Or did i miss that u replaced that too?

 

[94b2300ranger]

So at this point, the issue is that the truck won't start at all if it's hot/warmed up?

Did you get the idle issue fixed?

it doesn't have to be hot/warmed up, cold start it fires no problem, i can have it running for a minute and shut it off and try to restart it and it just cranks.

as for the idle issue, i'll work on that once i get the start issue fixed.

Ignition control module? Or did i miss that u replaced that too?

Negative I haven't replaced that yet. How would i go about testing it?

 

[86beater]

That im not too sure on how to test whether it is bad or not other than the process of elimination on everything that youve done so far, other than trying out a new one

 

[94b2300ranger]

That im not too sure on how to test whether it is bad or not other than the process of elimination on everything that youve done so far, other than trying out a new one

taking the ICM to napa, my buddy that works there can test it.

 

[BlackBII]

it doesn't have to be hot/warmed up, cold start it fires no problem, i can have it running for a minute and shut it off and try to restart it and it just cranks.

That is quite the mystery then.

When it won't start, is it not getting spark or fuel?

Either the injectors aren't firing or the spark plugs aren't sparking.

I can look in my service manual to see what the testing procedure is for the ignition module.

 

[94b2300ranger]

I wasn't able to test the ICM, so i picked up one from pick-n-pull along with a MAF, no change.

this is what i replaced so far, I replaced all of these items cause i didn't know the condition of them when i got the donor motor. Coil pack, plugs, wires, air temp sensor, IAC with new parts. I tested the injectors for resistance which all were between 16.0-.2 ohms as well as flow and leakage. Iv'e been just been replacing the coolant temp sensor with used ones, don't know why i haven't replaced it yet, but getting one tomorrow.

I have a fuel, vacuum and compression tester on order from Matco, should be on his truck Thursday, so i will test all those then. Will test for spark and fuel tomorrow if the problem persist, Cali is having a heat wave and I don't feel like working on it in this heat.

I'm wondering if the computer could be the culprit? I will open it up and see if i notice anything that doesn't look right as well.

I really appreciate your guy's time.

 

[BlackBII]

Testing the fuel pressure and for spark is a good idea. A weak or overheating fuel pump can be the cause of intermittent issues like this; I had that issue a while ago and tracked it down to the fuel pump.

There is also the crankshaft positioning sensor, which feeds the ignition control module for spark and tells the computer when to fire the injectors.

The service manual I have doesn't have the testing procedure for the ignition control module, but it might have it for the crankshaft positioning sensor. I'll check when I get home.