use a vacuum gauge to check exhaust.

run some seafoam through tank.

did you replace plugs? did you replace wires? checked dist./rotor?

clean throttle body.

check underneath the truck for rusted out brake lines, spring shackles, worn radius bushings etc. a lot easier to do before winter.

 

With a clogged cat, you might here some backpopping noises. A quick way to test it, is to remove the O2 sensor and unplug it. Removing it will leave a hole before the cats. Drive around the block and see if truck performs better. Of course, the vacuum gauge is the better way.

 

the trans mission is 4r7xxx

also i finally put gas in the rear tank and that fuel pump is very noticeably quieter than the front pump. the front won buzzz pretty good. since i did all the above changes in the first post (i got paid today) i wasn finally able to put a lot of gas in the first tank(had only a 1/4 tank for the longest time) and some gas in the rear tank. I drove the truck for about 15min and it did not act up once so i wonder if the front pump is weak when low on gas and that could be the studdering problem,

after work i'm going to
install the new vss sensor and
test the fuel pressure as soon as i can
if i have time take it to emissions testing and see if it will pass echeck

a clogged cat will cause the truck to fail emisssions right

I'll keep you guys posted

hopefully these problems are close to be solved

 

"a clogged cat will cause the truck to fail emisssions right"

not in ohio, it should pass easily.

make sure you have good gas cap. make sure they are tight, they do test that.

now in california, you may not have passed.

put seafoam into front tank with no more fuel in it. run that tank a little every day until it is almost empty. then fill to half tank.

a pump is bad or it isn't. you may have sludge in tank, or some water/condensation. try the seafoam first.

 

quicklook2 what about the #1 fuel pump being loud, in your theory do you think it is the sludge puting a strain on the pump, and that is why its louder

 

my front pump is louder than my rear, but it gives me no trouble.

i have a sable that was my dad's when he passed away and it was always really noisy.

and yes, a full tank would make it quieter.

from what you said they did not treat this truck well and that is why i am suggesting seafoam.

and i would put a can of seafoam in the back tank as well if it were my truck.

 

With running the truck they way they did for 2+ years, you might be in need of a new o2 sensor also.
Have you gone over all the vacuum lines?

The starting problem does sound fuel pressure related.
Primed but not running should be around 40psi, running ~32psi. Pull vacuum line off the pressure regulator and it should go up to around 40 again. If you see any fuel in the vacuum line or port on the regulator -replace it. Plug vac line back in and it should go back to ~32. Turn off engine and it should hold the pressure within 5psi for at least 30 seconds. Suspect a leaky injector if it doesn't.

Get the seafoam if you can, its good stuff!

Welcome to Ford-Trucks!
Popa Tim

 

ok guys i need some more help (phase two of the problem)sorry for so many questions at one time,but if i don't ask this way i'll forget things to ask.

First off the truck just barely passed emmissions today after work, here were the results.(Good News)

Emission Reading Units Limit Result
HC 133.3 PPM 134.0 PASS
CO 0.73 % 1.48 PASS
NO 15.8 PPM 1370.0 PASS
CO2 14.35 % N/A
Gas Cap Pressurization 28.40 In H2O 6.00 PASS

What can you guys make of those results

The truck was stuttering very bad(during the echeck too) any time i was giving it barely gas.
It would not run right unless I floored it or got the transmission to down shift. So I drove over to a Muffler Shop. They took a heat gun to the 2 cats. (Truck had been running for 45min straight)

There heat gun said that the 2 cats were 550degrees both of them, they said they are bad, because the second cat should have at least a 100degree drop in temperature.

The truck is now stuttering and driving the worse it ever has, so I get the truck home.

Well I took the VSS sensor out of the rear axle housing and cleaned it and put it back in.

The truck pulled a code 33 (EGR valve not opening detected).

(last Sunday, My buddy checked the EGR valve with a vacuum pump and said it was good and i also cleaned it out and put it back on)(EGR valve position sensor has been replaced)

Do you guys think the cats being bad are causing the code33 on the EGR valve.

The truck ran the same way on both the fuel pumps, I cannot see both fuel pumps being bad in the truck

I also got my fuel pressure tester back tonight, where is the test port located at(its on the fuel rail right), so I can try to test fuel pressure regulator and fuel pump tomorrow on my lunch break.

Thanks again.
Nate

 

Yes, the valve is on the fuel rail. Test the pressure while the engine is idling. Also, leave the gauge on after you turn off the engine. Check the bleed-down rate. Post back results.

The cat shouldnt affect EGR valve. If EGR is working, and EVP (sensor) is new, check the wiring or the EVR could be bad. Remove the EVP and push the pintle all the way down. Tape it so it stays pushed in. Now, run a KOEO test and you should get code 34. This confirms wiring is proper.

 

guys

how do you check the exhaust with a vaccum gage and how much does one of these cost, is this the same thing as a vaccum pump

 

no.

the cost should be around $30. i have had one for so long i do not remember how much it costs.

a vacuum gauge connects to a good intake vacuum source. it is well covered in most manuals on how to use it. it is very old school in that it has been around and used for many years. it tells a ton about your engine.

any gauge should come with all the instructions.

for exhaust: when at idle the gauge will read normal, on acce,eration the gauge will drop to zero if a clogged exhaust is present.

 

quicklook2, if the exhaust is not clogged, what will the gage read roughly

 

Around 20inHG at idle

 

so it should read 20inHG now matter what the engine rpm is on the gauge then

 

It should fall when you open the throttle, and then slowly come back up. Anything around 20 at IDLE is normal. It should be steady, and not fluctuate at a constant RPM.