My 1987 fox body 5.0 motor wont goes pass idle when trying to rev it

not a fox body

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Apr 16, 2019
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Oh the painful reality of the internet truths! 94psi? :confused:
i don't think so unless you have a jet pack strapped to the hatch!
more like 42+/- koeo and 32-34 koer. I'm not trying to run you off just because this is a miata, it is 'Ford Tough' now, I'd look into a in tank type pump around maybe 240 lph, I'm going to guess here that the system is a one way affair and does not have a return line, right.
How bout a shot of the car, engine pics too, see if we can poke fun, I mean, help you spot any other troublesome issues.
Well see I went to the auto parts store and asked how many Lph and the dude came back with 94 psi and I was like what but I don’t think I have a return line I might I will check but i don’t know yet we will see
8B0C81DE-5508-4360-AC87-C022CDEA5E20.jpeg
2ED84D76-B82D-46FC-A6E2-17918937EE08.jpeg
 
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Blown88GT

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Well I found out that my fuel pump only puts out 4 to 7psi and I herd that I need 94 psi in general I guess I don’t know I will look more into it
That's the problem, the herd won't move without more pressure. You need Rowdy Yates (aka, Clint Eastwood) to move the herd.
It is not 94 psi; it's 39 psi.
Stock fuel pump flows 88 liters per hour.
 

not a fox body

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Apr 16, 2019
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orangevale ca
Oh the painful reality of the internet truths! 94psi? :confused:
i don't think so unless you have a jet pack strapped to the hatch!
more like 42+/- koeo and 32-34 koer. I'm not trying to run you off just because this is a miata, it is 'Ford Tough' now, I'd look into a in tank type pump around maybe 240 lph, I'm going to guess here that the system is a one way affair and does not have a return line, right.
How bout a shot of the car, engine pics too, see if we can poke fun, I mean, help you spot any other troublesome issues.
Well see I went to the auto parts store and asked how many Lph and the dude came back with 94 psi and I was like what but I don’t think I have a return line I might I will check but i don’t know yet we will see
?hash=9ea88175436f2449d791b86e14db8f4b.jpg
 

Mustang5L5

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Well see I went to the auto parts store and asked how many Lph and the dude came back with 94 psi and I was like what but I don’t think I have a return line I might I will check but i don’t know yet we will see
8B0C81DE-5508-4360-AC87-C022CDEA5E20.jpeg
2ED84D76-B82D-46FC-A6E2-17918937EE08.jpeg

I can see the return line in the pic
 

Mustang5L5

Put lubricant all over the balls
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Where cause I’m still having problems I don’t know still but today I’m going to be taking off the hole intake and stuff so I can clean sup and look for vacuum leaks and stuff but I personally don’t see the return line

These two stainless lines connect to the fuel rail. One is primary other is return.

Take a better pic of the area. Should be a schrader valve in that area to hook a fuel pressure guage up and measure pressure. Should be 39 psi vacuum off regulator

IMG_4073.PNG
 

not a fox body

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Apr 16, 2019
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orangevale ca
These two stainless lines connect to the fuel rail. One is primary other is return.

Take a better pic of the area. Should be a schrader valve in that area to hook a fuel pressure guage up and measure pressure. Should be 39 psi vacuum off regulator

IMG_4073.PNG
Ok well I pulled the whole intake off expect that manifold but I pull the penla off and the throttle body apart and cleaned cause it was nasty and I started to check wires that were chewed by rats but I should have it back on tomorrow and I hope maybe it will change the problem a little bit
 

not a fox body

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So I got it back on and it didn’t change anything I still don’t know what’s wrong and I haven’t tried pulling codes cause still thinks it’s a easy fix I hope at least
 

jrichker

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So I got it back on and it didn’t change anything I still don’t know what’s wrong and I haven’t tried pulling codes cause still thinks it’s a easy fix I hope at least
Dump codes sticky

Dumping the codes is very simple...Look at the top of the 5.0 Tech forum where the sticky threads are posted. One of them is how to dump the computer codes. Codes may be present even if the CEL (Check Engine Light) isn’t on. You don’t need a code reader or scanner – all you need is a paper clip, or if your lady friend has a hair pin, that will do the job.
I highly suggest that you read it and follow the instructions to dump the codes. http://www.stangnet.com/mustang-forums/threads/how-to-pull-codes-from-eec4.889006/
 

jrichker

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so now I have a knock I but i sounds like a stuck valve i don’t know and it happened right after I replaced the spark plugs
It is time to beg, borrow or buy a vacuum gauge to troubleshoot the problem. Most auto parts stores will rent or load one if you have a credit card.

Vacuum Gauge readings
attachments\606429
 

jrichker

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Where's the gauge reading for a high lift cam with a bunch of overlap? My valve timing ain't late.
I never encountered that combination, so I have no data to base a diagram of what it looks like.

If you have such a combination and are willing to provide the data for it, I will gladly create another diagram and add a note to the diagram crediting you with providing the data for it.

The data I would need is what the vacuum gauge readings look like at 650-725 RPM base idle and again at 1100-1200 RPM. Thanks in advance for being a team player and working to help your fellow enthusiasts enjoy their cars.
 

CarMichael Angelo

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I never encountered that combination, so I have no data to base a diagram of what it looks like.

If you have such a combination and are willing to provide the data for it, I will gladly create another diagram and add a note to the diagram crediting you with providing the data for it.

The data I would need is what the vacuum gauge readings look like at 650-725 RPM base idle and again at 1100-1200 RPM. Thanks in advance for being a team player and working to help your fellow enthusiasts enjoy their cars.

I'll get that for you just as soon as I can Joe, anything for the common good of the team. Count me in!:nice:
 
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not a fox body

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Apr 16, 2019
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orangevale ca
I never encountered that combination, so I have no data to base a diagram of what it looks like.

If you have such a combination and are willing to provide the data for it, I will gladly create another diagram and add a note to the diagram crediting you with providing the data for it.

The data I would need is what the vacuum gauge readings look like at 650-725 RPM base idle and again at 1100-1200 RPM. Thanks in advance for being a team player and working to help your fellow enthusiasts enjoy their cars.
So it was idled at 1000rpm to 1100rpm and there vacuum was 20 the whole time