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Did you use a infrared temp thermometer gun? I bought one which helped but I had to be quick b/c the two dead header tubes quickly heated up at idle and made it difficult to tell which ones were dead and which ones weren't but there was a difference in temps when I rev'd it up.

ks
 

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Have you done a cylinder balance test?
One of the KOER tests.

That should tell you if the cylinders are contributing or not.
 

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Discussion Starter · #83 ·
Did you use a infrared temp thermometer gun? I bought one which helped but I had to be quick b/c the two dead header tubes quickly heated up at idle and made it difficult to tell which ones were dead and which ones weren't but there was a difference in temps when I rev'd it up.

ks
Yes. It's real tricky to say the least. I don't trust it 100%.
 

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Yes. It's real tricky to say the least. I don't trust it 100%.
Another way to do it is to lightly spray water on each tube but it's best if someone operates the throttle when you spritz water on each tube. Get the water ready and have someone start the car then have them rev it to around 3K. As soon as the RPM's go up spritz water on each tube on one bank. The banks that are firing will boil/steam the water off instantly while the cooler one(s) will take just an extra few seconds. Keep spritzing the tubes on the one bank until you are convince that they are/are not firing. This should take about 15 seconds then let it all cool off before doing the other bank.

ks
 

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The injector is only telling you if they are electronically grounding. Not necessarily spray pattern if there is a clog. If it is fuel injector you can move them and the problem will follow.

That is how I found my issue 2 years ago. I had an injector that was not spraying properly.
 

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Discussion Starter · #87 ·
Another way to do it is to lightly spray water on each tube but it's best if someone operates the throttle when you spritz water on each tube. Get the water ready and have someone start the car then have them rev it to around 3K. As soon as the RPM's go up spritz water on each tube on one bank. The banks that are firing will boil/steam the water off instantly while the cooler one(s) will take just an extra few seconds. Keep spritzing the tubes on the one bank until you are convince that they are/are not firing. This should take about 15 seconds then let it all cool off before doing the other bank.

ks
Good idea!
 

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Discussion Starter · #88 ·
The injector is only telling you if they are electronically grounding. Not necessarily spray pattern if there is a clog. If it is fuel injector you can move them and the problem will follow.

That is how I found my issue 2 years ago. I had an injector that was not spraying properly.
Yup; I know. BTDT.
 

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Discussion Starter · #89 ·
Leak down test went perfect. It's a very healthy engine. When I pressurized cyl #5 , I pulled cyl #6 plug. There is no air passing from 5-6. I saw no bubbles in the coolant either.
 

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350-400 give or take.
All the header primaries measure the same, Even the ones that aren’t firing? Did you measure a couple inches away from the flange?

The bad cylinders will be under 200* if you start the engine, run In for a 15 seconds or so and then check. That is if they’re not firing.
 

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Are your fuel trims showing a difference between the banks?

If you are missing 2 cylinders on one bank, I would expect that bank to be indicating significantly leaner than the other.
 

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Discussion Starter · #92 ·
Are your fuel trims showing a difference between the banks?

If you are missing 2 cylinders on one bank, I would expect that bank to be indicating significantly leaner than the other.
I'm running a turbo and have one WB in the down pipe.
 

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I'm running a turbo and have one WB in the down pipe.
I see.
I thought the whole point of turbo is to put the car on jack stands because it'll never run..... I keed, I keed.

So, good compression, good leakdown, fuel on plugs, good spark when out of engine (can't see spark inside cylinder), tried multiple plugs.

If plugs are wet with fuel and your compression and leakdown results are good, to me it seems like you are not getting spark when the plugs are installed.

Are you using any antiseize on the plug threads?
 
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Discussion Starter · #94 ·
I see.
I thought the whole point of turbo is to put the car on jack stands because it'll never run..... I keed, I keed.

So, good compression, good leakdown, fuel on plugs, good spark when out of engine (can't see spark inside cylinder), tried multiple plugs.

If plugs are wet with fuel and your compression and leakdown results are good, to me it seems like you are not getting spark when the plugs are installed.

Are you using any antiseize on the plug threads?
I think I may have found the issue. What started out sounding like a small exhaust leak has developed into a knocking inside of the passenger valve cover. I'm thinking I have a loose rocker or two.
 

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Discussion Starter · #96 ·
Why do you suspect 5 & 6?
Have you pulled all plug wires and they were the only 2 not to react?



What happened to Indy? I noticed he hasn’t posted lately.
To be honest; I've done so many things that I don't know which way is up. Lol.
Indy was banned quite a while ago.
 

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I knew I'd be hearing from you and you're right. I wish you weren't.
to be honest, with all the crap in the way, Im sorry that I was. I really hate taking off valve covers now.

invest in trick flows valve cover studs. worth there weight in gold.

I hope you found the problem. if it is a loose rocker arm, after you bring it on the base circle and take the lash out of the pushrod, then give it your required preload, back it off 1 or 2 flat sides, run the set screw down until it makes contact, then re tighten the nut. this locks down the rocker and i can guarantee it will never come loose again. gl
 

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Discussion Starter · #100 ·
to be honest, with all the crap in the way, Im sorry that I was. I really hate taking off valve covers now.

invest in trick flows valve cover studs. worth there weight in gold.

I hope you found the problem. if it is a loose rocker arm, after you bring it on the base circle and take the lash out of the pushrod, then give it your required preload, back it off 1 or 2 flat sides, run the set screw down until it makes contact, then re tighten the nut. this locks down the rocker and i can guarantee it will never come loose again. gl
I actually use ARP vc studs. They are very handy. I've never had a rocker come loose so maybe I had a senior moment. I'll try that tightening method. Thanks.
 
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