Solving mysterious miss in 92' MTX (testing injector connectors)

[stangeater]

I was thinking on it, as long as the indent on the cam sprocket lines up with the line on the back of the cover?

I'll go get some better pics for you, gimme two minutes..

EDIT:

Here our face on shots, the teeth are were they are supposed to be as far as I can tell.





Does knowing that cylinders 1,3,4,5,6 are fouling their plugs help me diagnostically at all?

Also, isn't it very possible that those grounds being so mucked up before could have been the issue?

IDK where the fuse for the fuel pump is but I'm gonna go search it up right now..

The plugs are getting fouled because of the miss...... You should have tried running the car after cleaning those grounds...that could have been the problem.
The wires you found up by the battery were from the alarm system. It works fine, but I forgot how to set it, so I just unplugged it.
You know, you can ask me questions about this stuff.......??

 

[stangeater]

Also, more helpful info........ The car was missing before changing the plugs. That was in the original post that you linked.

 

[Bob Gervais]

Also, more helpful info........ The car was missing before changing the plugs. That was in the original post that you linked.

Sounds as if you may be taking some of this the wrong way. I never intended that, nor do I think the current owner intends that.

Nothing wrong in retracing steps...

 

[stangeater]

Sounds as if you may be taking some of this the wrong way. I never intended that, nor do I think the current owner intends that.

Nothing wrong in retracing steps...

NOOOO!! I'm sorry! I wasn't meaning to come across that way! I totally agree with retracing my steps for sure! I'll be SO glad to finally know what the culprit is! If I had the time to mess with this myself, I'd still own the car! I already miss it!:sun:

 

[vortex2450]

I got what the gauge does but I don't have the time or gas for an out of the way 1-1/2 hour round trip to get one. I have school tomorrow so I'll stop by Advance and see what I can work out.

If 5k ohms per foot is acceptable then I'm ruling out wires.

Hey stangeater! I was actually in the middle of writing you an update email when I jumped over to this thread.I guess if your on here this will be easier to follow right? Well, I've been very busy with tearing into the engine for the past 2 days as if the pics don't already say that lol.

It's starting to get to me at this point...

The road grime for shipping is leaving some really tough to clean mineral spots btw, but despite being a rolling chassis I'm already in love with the car.

When I asked about the plugs I meant it as in it shows which cylinders are running worse off than the others and maybe seeing that cylinder 2's plug looked right as rain might lead to a diagnosis but I haven't got the clue where to go with that.

For $hits and giggles i swapped the NGK plug into my ATX and although I didn't clean them off they ran fine so I ruled them out officially.

I never meant that as in stepping on your toes

Hmm I am supposed to be getting a solid 12v to the injectors? I was thinking so but figured since all were the same I was golden.

Anyways, I got the new injectors installed and buttoned up. I also checked for any other grimy grounds and swapped in cleaned Autolite Platinum plugs and then reassembled the engine.

Now I went from a miss to no fire at all
I did smell gas after turning it over multiple times but then again I got gas all over me.

I'm sure I missed something somewhere, I cleaned all the ground points to the DIS and checked them all vigorously with the multimeter.

It was going on 12 solid hours inside that engine bay so I called it at that.

Tomorrow I'm gonna dismount the intake again and dig in for round 2.
First stop CCRM..

EDIT: After a great night's rest and some brainstorming this 3.56v at the connectors is pointing out the CCRM or one of the wires going to/ coming from it as being highly suspect, no?

To recap:
I finished cleaning up any bad grounds I found ( total of 3 ), installed the new injectors, buttoned up the fuel system and systematically reinstalled the intake in the same fashion I took it off.

It will now crank fine but no fire,
I stuck my head out of the door while turning it over and couldn't hear the definitive sound of the injectors clicking.

I took the Autolite plugs back out and cleaned the electrode and the boot connection, same thing. Also did the same with the NGK plugs and still just cranking for nothing.


I'm waiting on my dad to get home so he can help me check for spark at each cylinder. I'm willing to bet after almost everything in the ignition path has been looked over I should be getting full spark. I will also listen very closely for the injectors while he turns it over.

If I have a good spark on all the wires I'm going to remove the intake again, by that time I 'll probably have to make my way to town for school and I'll pick up a compression gauge and a noid light.

Once I get back, I'm going in after the CCRM and the wiring to it but I don't really know where and what I'm going to be looking for, anyone wanna clue me in here?

Thanks,
Josh

 

[vortex2450]

does anyone wanna give me the low down on the CCRM?

I have no idea what I'm looking for and my searches are proving fruitless..

 

[Bob Gervais]

What lowdown are you looking for? I mentioned above about which pin to check for 12v.

 

[vortex2450]

What lowdown are you looking for? I mentioned above about which pin to check for 12v.

As in I need a quasi-specific placement for what I'm looking for. I'm sure I'll see it once the intake is back off but I like going in educated, haha.

 

[Phoenix]

I got what the gauge does but I don't have the time or gas for an out of the way 1-1/2 hour round trip to get one. I have school tomorrow so I'll stop by Advance and see what I can work out.

If 5k ohms per foot is acceptable then I'm ruling out wires.
Hey stangeater! I was actually in the middle of writing you an update email when I jumped over to this thread.I guess if your on here this will be easier to follow right? Well, I've been very busy with tearing into the engine for the past 2 days as if the pics don't already say that lol.

It's starting to get to me at this point...

The road grime for shipping is leaving some really tough to clean mineral spots btw, but despite being a rolling chassis I'm already in love with the car.

When I asked about the plugs I meant it as in it shows which cylinders are running worse off than the others and maybe seeing that cylinder 2's plug looked right as rain might lead to a diagnosis but I haven't got the clue where to go with that.

For $hits and giggles i swapped the NGK plug into my ATX and although I didn't clean them off they ran fine so I ruled them out officially.

I never meant that as in stepping on your toes

Hmm I am supposed to be getting a solid 12v to the injectors? I was thinking so but figured since all were the same I was golden.

Anyways, I got the new injectors installed and buttoned up. I also checked for any other grimy grounds and swapped in cleaned Autolite Platinum plugs and then reassembled the engine.

Now I went from a miss to no fire at all
I did smell gas after turning it over multiple times but then again I got gas all over me.

I'm sure I missed something somewhere, I cleaned all the ground points to the DIS and checked them all vigorously with the multimeter.

It was going on 12 solid hours inside that engine bay so I called it at that.

Tomorrow I'm gonna dismount the intake again and dig in for round 2.
First stop CCRM..

EDIT: After a great night's rest and some brainstorming this 3.56v at the connectors is pointing out the CCRM or one of the wires going to/ coming from it as being highly suspect, no?

To recap:
I finished cleaning up any bad grounds I found ( total of 3 ), installed the new injectors, buttoned up the fuel system and systematically reinstalled the intake in the same fashion I took it off.

It will now crank fine but no fire,
I stuck my head out of the door while turning it over and couldn't hear the definitive sound of the injectors clicking.

I took the Autolite plugs back out and cleaned the electrode and the boot connection, same thing. Also did the same with the NGK plugs and still just cranking for nothing.


I'm waiting on my dad to get home so he can help me check for spark at each cylinder. I'm willing to bet after almost everything in the ignition path has been looked over I should be getting full spark. I will also listen very closely for the injectors while he turns it over.

If I have a good spark on all the wires I'm going to remove the intake again, by that time I 'll probably have to make my way to town for school and I'll pick up a compression gauge and a noid light.

Once I get back, I'm going in after the CCRM and the wiring to it but I don't really know where and what I'm going to be looking for, anyone wanna clue me in here?

Thanks,
Josh

I didnt follow the whole story , but this is BS. This is one thing Ive learned through the years , swap with good ones instead. The ohmage checking thing isnt an exact science. Ive seen bad wires with good ohms in the past.

Secondo , the CCRM only powers the fuel pump , and it also powers the ECM , if you have power through those wires then its not it. A missfire wont be caused by a CCRM , but a no start (no fuel) thats another story.

For regular missfires you need to look for: DIS , Coil , wires , plugs.

For nostart cause of no spark: DIS , Cam sensor , crank sensor , DIS not tight enough or only 2-3 bolts installed , Missing or bad ground from the ground strap behind the intake....

Thats the common stuff.

We rarely see any electrical issues due to wires or bad PCM.

Please ignore some of this stuff if its already been said or tested , Ive only read this thread between the lines...

 

[Bob Gervais]

As in I need a quasi-specific placement for what I'm looking for. I'm sure I'll see it once the intake is back off but I like going in educated, haha.

Oh! The CCRM is the box mounted to the top of the radiator support. Take off the plastic guard on your radiator support, and you'll see the box. It's black, and about 4x5".

 

[Bob Gervais]

I didnt follow the whole story , but this is BS. This is one thing Ive learned through the years , swap with good ones instead. The ohmage checking thing isnt an exact science. Ive seen bad wires with good ohms in the past.

Secondo , the CCRM only powers the fuel pump , and it also powers the ECM , if you have power through those wires then its not it. A missfire wont be caused by a CCRM , but a no start (no fuel) thats another story.

For regular missfires you need to look for: DIS , Coil , wires , plugs.

For nostart cause of no spark: DIS , Cam sensor , crank sensor , DIS not tight enough or only 2-3 bolts installed , Missing or bad ground from the ground strap behind the intake....

Thats the common stuff.

We rarely see any electrical issues due to wires or bad PCM.

Please ignore some of this stuff if its already been said or tested , Ive only read this thread between the lines...

Perhaps reading the entire thread would be of some help.

Wiring diagrams show that the injector harness gets power from the CCRM, a splice inline with power to the EEC.

I've seen bad ignition wires right out of the box. Testing them is a good start. Granted, there could be breaks in the insulation that will cause grounding issues when the car's running, but those should be blatantly apparent.

The CCRM will not cause a misfire, you're correct on that, however if you had read the whole thread you'd see that he's only getting 3.56v to the injector harness. I'm thinking that could be an issue....

 

[Phoenix]

Allright , I just did , and that voltage looks weird , I will pull my books to see whats what.

Meanwhile I got this to the OP , the pin charts for the CCRM

http://www.shospeed.com/pics/SHOCCRM.pdf

 

[vortex2450]

I didnt follow the whole story , but this is BS. This is one thing Ive learned through the years , swap with good ones instead. The ohmage checking thing isnt an exact science. Ive seen bad wires with good ohms in the past.

Secondo , the CCRM only powers the fuel pump , and it also powers the ECM , if you have power through those wires then its not it. A missfire wont be caused by a CCRM , but a no start (no fuel) thats another story.

For regular missfires you need to look for: DIS , Coil , wires , plugs.

For nostart cause of no spark: DIS , Cam sensor , crank sensor , DIS not tight enough or only 2-3 bolts installed , Missing or bad ground from the ground strap behind the intake....

Thats the common stuff.

We rarely see any electrical issues due to wires or bad PCM.

Please ignore some of this stuff if its already been said or tested , Ive only read this thread between the lines...

So then you would say I'm premature in ruling it wires?
I have an old working set from my ATX so I'll swap those just to see but they aren't in very good shape.

What we were getting too in this thread was that I am only getting 3.56v @ key on at all 6 injector connectors which Bob Gervais pointed out as not right and I should be getting 12v at the connector. So that's why the CCRM has become a point of interest.

In my mind if the old injectors suddenly weren't getting the 12v they need and being as their range of resistance is wide maybe a few of those were still able to open enough to allow fuel into the the cylinder, I didn't order the injectors per cylinder but I know that the spark plug from cylinder #5 came out clean and that one of the old injectors had a much lower impedance than the others. (When the issue starting the PO was driving and it was like the flip off a switch, similar to what would happen if a wire shorted because component failure is usually a slow death from my understanding.)

This is all theory but I'm being as thorough in this as a19yr old student who's barely dug this deep into a SHO can.


The things done before I got the car included all that you mentioned. (Top of the thread)

The No start issue happened after I took the intake off and replaced the fuel injectors and cleaned the ground in the valley, the ground for the intake, and the ECU ground near the battery.

Being as I put it all back together late into my 12 hour day yesterday I'm willing to bet I fouled up , albeit I don't know where.

Or maybe in correlation with my theory the new injectors with their high impedance and tight tolerances just aren't firing at all.

I'll have answers soon, I'm going to go check for spark now as I haven't done that yet. I'm also going to listen for that definitive "click" I know the injectors in my ATX make.

I also purchased a compression tester so once the intake is off I'll have those results up here as well.

Thanks,
Josh

EDIT: The forum is playing tricks on me so my post is mistimed. Thanks for the diagram, that's definitely a useful resource.

 

[Bob Gervais]

Josh, I'd say you're on the right track here.

Plug wires, as Phoenix pointed out, can't always be effectively tested just for resistance. If you know the old wireset you have worked fine, it may be worth swapping those on to find out if that helps your issues. However, I don't think that's the issue, based on the fact that it was misfiring before and after the PO changed the plugs and wires.

Good luck with further investigations, you're doing just fine so far.

BTW, that multimeter you're using to test with is set on DC voltage, correct? (just figured I'd ask!)

 

[lowc]

following this thread and checking the proper testing through the ford site i use it's sounding more like a ccrm issue to me exspecialy with that voltage being so low.

 

[vortex2450]

Thanks guys. I keep replaying the scenario over and over in my head and it's all falling into place. It's great to have so much encouragement and information from you all.

All 6 wires have a strong park through the NGK plugs which I cleaned up. I tested everyone twice and got some feedback from the engine myself as well...

I'm positive the ignition is all systems go.

Now, however, I did not hear any "click" "click" "click" even with my head pushed as close to the injectors as I could get.

I'm half way through testing all the cylinders for compression, the battery starting complaining about having to turn that engine over and over so I've got it juicing up on the charger now, expect compression #'s within the hour.

As for the CCRM, am I testing pin #11 or pin #24?

I'm going to grab my multimeter and get at that after I finish testing the compression.

EDIT: Failed the compression test, no compression at cylinder #2 , here's the others:

1. 195 psi 2. 0psi 3. 193 psi

4. 185psi 5. 190psi 6. 187psi

My heart sank when that needle didn't move. I can only guess I'm looking at a stuck valve/split shim, right?
Probably a result of the miss...

I didn't get to testing the wires out from the CCRM yet, it's just too cold for my hands and it's late.

I would like to say there's light at the end of the tunnel but now even when I solve the miss I still got a cylinder with a bad valve....

 

[Phoenix]

0 PSI on number 2.....

Sounds like a burnt/bent/stuck valve , and it would explain alot of things.

On a side note Ive checked the Helms books , they talk about the ECM controlling the injectors sending a ''signal'' to them without saying the Voltage numbers anywhere. It also said it controls the strength of the signal to add more fuel , which means either its a higher voltage or it stays on longer....

Maybe it time to remove the rear valve cover. maybe you can see something from there , who knows.

 

[Bob Gervais]

In my 92 manual, it says pin 24. However, you're looking for the red wire out of the ccrm.

I'd test #2 again, just to be on the safe side. Test it dry, and again with some oil squirted into the cylinder. If the compression raises at all with oil in the cylinder, it's piston ring related. If it doesn't raise, it's valve related.

At this point, no compression in a cylinder will cause your miss. You'd still need to figure out the low voltage to the injector harness issue, but if there really is 0 compression in #2, you'll need to figure out why, and figure out what you're going to do about it.

 

[Bob Gervais]

0 PSI on number 2.....

Sounds like a burnt/bent/stuck valve , and it would explain alot of things.

On a side note Ive checked the Helms books , they talk about the ECM controlling the injectors sending a ''signal'' to them without saying the Voltage numbers anywhere. It also said it controls the strength of the signal to add more fuel , which means either its a higher voltage or it stays on longer....

Maybe it time to remove the rear valve cover. maybe you can see something from there , who knows.

I'm really hoping it's a valve issue, maybe an ejected shim or something that could be repaired fairly easily.

The injectors have 12v to them, in run and start positions of the ignition. The PCM signals the ground to fire them. Pulse width controls how long they're open for, meaning that the PCM would ground the injectors for a longer period of time if more fuel is needed.

 

[vortex2450]

thanks for making "burnt" and "bent" my first two options phoenix, that's just brightens my day :angelnot:

All I'm going to do about it right now is whine. I don't have any tools for valve work and I'm out of money now.. I am taking the valve cover off AFTER I fix the issue with the injector harness.

And I'm pretty certain the low voltage is the primary issue here. I'm going to test the wire as close to the CCRM and it I get 12v that tells me it's in the harness/splice somewhere. I'm going to find a point past the splice to test and it I get 12v there I know it's in the splice.

If I can't find the splice, lets be real here, there are a lot of harness going every which direction in the engine bay, I'm going to run a whole 12v supply of my own.

On the flip side, if I discover the valve is a " relatively easy" fix, would anyone be willing to lend me tools in good faith?