DeltaBravo

Hello yotatech,

First, I am new to this forum. I've owned my 1994 Pickup 22RE for the past 5 years. Great truck, has never left me stranded...always starts up and just keeps going, until recently...

It will crank over but not start. Here are things I've checked.
1. I have a CEL with the ignition on.
2. I don't have any codes.
3. I verified spark at the end of all the plugs wires. As well as the rotor turns during cranking.
4. I can smell fuel from the exhaust after cranking for a solid 5 second count.
5. Verified fuel pump works with ignition ON and moving the AFM door slightly OPEN.
6. Verified AFM readings, plus I swapped it out with another know good one...no change.
7. Checked for good grounds. One from the battery, one from the engine.

So...I know I have spark and I know I am getting fuel and the AFM doesn't seem to be the issue. Any other sensors/ reasons that would prevent the motor from starting?

Thanks in advance.

Co_94_PU

iTrader: (-1)

Combustion requires spark, fuel, and compression. Unless you're leaving out recent work from the problem description your next step is the compression check.

coryc85

I don't think you've proven that your injectors are firing, the fuel smell could be from your cold start injector perhaps. There is a ground from firewall to rear valve cover area, there is also a ground that goes to the intake manifold, I'd check to see if that ground to the intake manifold got broken somehow. You didn't mention any work done, so was this a one day it runs, next day it doesn't kind of thing or did it sit for a while or what?

DeltaBravo

Four days ago, I was driving on the freeway doing about 70mph and then suddenly lost power, I coasted to the shoulder and tried to start it back up, but it would only crank over. Called AAA and got a tow home.


I will double check my grounds.
Compression is good. Most recent work- I replaced the front seal due to it leaking...don't think that would have any correlation...but ya never know!
No previous issues. Over 255,000 miles.


Since then

DeltaBravo

so...

I pulled all the spark plugs, double check compression...all around 175.

But...I think I am leaning toward spark as my problem now. I had all the spark plugs pulled and connected to their respected wires. I rigged up a temp ground to ground the spark plug while my son cranked the engine over for a good 5 second count. I did this for all of them. I noticed something odd...I would see a spark or two, sometimes three but never more. Every one did the same things. Now I think it's either my coil or igniter. Any way to check the igniter?

DeltaBravo

HA!

It was the coil. The old one provided just enough spark to take me down this 3 day long rabbit hole. Also, don't believe the 'ohms' check...in my case, it passed that check as well.

Co_94_PU

iTrader: (-1)

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glas you found the problem, and thanks for updating it helps others that wander across the thread via searching.

a few things regarding coils.

One they are filled with magic goo, if they show signs of cracks or leaking they need replaced, also the goo will vaporize and you'll find they are lighter than a new one and might not show any leaks.

Two, they are susceptible to failure when heated, bring them up to near engine bay temperature and the resistance will change, likewise it changes due to extreme cold.

And finally make sure your ignition gaps are all within spec, these all add up and increase the voltage required to bridge the gaps and the coil has a finite limit which when exceeded begins to deteriorate the coils and vaporize the goo.

The sub text is to verify your gaps before using any new parts, and always change your cap and rotor at the same time along with your plug wires.