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WHAT am I miSSing

  • Thread starter Thread starter jonbacon
  • Start date Start date Sep 30, 2011

jonbacon

Member
Sep 12, 2011
125
1
18
Sep 30, 2011
#1
  • Sep 30, 2011
  • #1
So i have myt o2's in and everything looks good, no cel. I set idle and had tps at 1.1 ( for some reason cant get it to .9) it takes 2 or 3 times to fire up and throttle it before it will idle at 700-800. sounds good, idles good once cranked. But when I go to drive it, she will cut out on me at 10mph, no power at al till I let off the gas?? Man i dont know what I'm missing?? I guess the TPS is wrong
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,265
17,952
224
Massachusetts
Sep 30, 2011
#2
  • Sep 30, 2011
  • #2
Now that you installed the O2's, get the engine up to temp, turn it off and then run the check engine codes. Get the KOEO and CM codes.

Then fire it up and get the engine running codes. Now with O2 sensors in, you should be able to get much more accurate representation of how car runs. THEN perform a cylinder balance test. .


I'm sure you'll have a few codes and hopefully you get a passing on the Cylinder Balance test indicating all 8 cylinders are firing equally. That's when you can start to address the codes 1 by 1.

As for the TPS, 1.1 is right at the limit. You might want to try slotting one of the holes slightly so you can get it down a bit just to get you some breathing room based on wire resistance values changing on hot and cold days and with rising engine temp.

A bad TPS and/or bad ECT can cause your symptons...but both will have a code generated for them. That's why guessing is a poor choice that just costs you $$$. If it's bad, there will be a code for it
 

jonbacon

Member
Sep 12, 2011
125
1
18
Sep 30, 2011
#3
  • Sep 30, 2011
  • #3
I dont have any codes poppin gup. theresno light on. the only tim eit comes on is when I try to drive it. its sits and idles fine, but when i go to drive it...cuts out on me until i left off the gas..
 

skunk21

Active Member
May 22, 2007
1,203
3
36
Taxachusetts
Sep 30, 2011
#4
  • Sep 30, 2011
  • #4
are you using a scanner? you should atleast get the all is good code. you doing the test right? these cars will store codes with out the light being so that isn't an indicator. also what is your FP ?
 

jonbacon

Member
Sep 12, 2011
125
1
18
Sep 30, 2011
#5
  • Sep 30, 2011
  • #5
i HAVE THE 4135 CODE READER.... I havent checked but I will tonight.. FP??? not sure what that is, still kind of new to this.. put the o2's in and light went off. just wont crank at first like it should have to give it gas for a minute if it will even let me. kind of push the gas but no responce.. so im guessing the tps is off. I have drilled out the holes in it probably as far as i can. i must not be setting it right.. I hav the muit reader is set to 500, then shows me 1.1
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
2,652
223
gainesville
Sep 30, 2011
#6
  • Sep 30, 2011
  • #6
FP is fuel pressure. if your pump is crapping out or you have junk in the lines you could possibly be chasing the same issues. Run the car up to temp like said and check for codes. stop guessing and do the things the car is telling you to do. Ive been in your shoes. While it sucks and its tedious. Going through the wont idle check list will get your car running the way its supposed to. If you dont pull any codes tonight clear the computer and reset your idle. See how it runs after that. Sometimes a stored code will cause issues even after you have corrected the problem.
 

skunk21

Active Member
May 22, 2007
1,203
3
36
Taxachusetts
Sep 30, 2011
#7
  • Sep 30, 2011
  • #7
jonbacon said:
i HAVE THE 4135 CODE READER.... I havent checked but I will tonight.. FP??? not sure what that is, still kind of new to this.. put the o2's in and light went off. just wont crank at first like it should have to give it gas for a minute if it will even let me. kind of push the gas but no responce.. so im guessing the tps is off. I have drilled out the holes in it probably as far as i can. i must not be setting it right.. I hav the muit reader is set to 500, then shows me 1.1
Click to expand...

your TPS is probally junk. why did you even mess with it . I asked about the FP ( fuel pressure ) it could be an issue and you are chasing the wrong problem.

We have a source at the top of our tech page called stickies filled with tons of info. The title might not hit right on yours but they could have helpful info.

gives these a read...and please read them

http://www.stangnet.com/mustang-forums/825424-adjusting-your-tps-0-98v-not-necessary.html



http://www.stangnet.com/mustang-for...o-start-checklist-fuel-injected-mustangs.html

http://www.stangnet.com/mustang-forums/698148-help-me-create-surging-idle-checklist.html

http://www.stangnet.com/mustang-forums/786928-eec-iv-trouble-codes-quick-reference-pdf.html

and just in case your next question is one of these, here ya go ..

http://www.stangnet.com/mustang-forums/636360-whats-up-everyone.html?showpost=

^ this is a thread of the list of mods by priority.

http://www.stangnet.com/mustang-for...ug-5-lug-brake-conversion-upgrade-thread.html

now go grab a beer, coffee, water, tea or what ever it is you drink and sit back and read the info it is a wealth of it and it will help get you in a direction or atleast one we can better help with.


 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
2,652
223
gainesville
Sep 30, 2011
#8
  • Sep 30, 2011
  • #8
^ great post. I try to keep my BS to a minimum in tech so no sarcasm here. Every bit of info that you need to get your car straight id in these links.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,265
17,952
224
Massachusetts
Sep 30, 2011
#9
  • Sep 30, 2011
  • #9
jonbacon said:
I dont have any codes poppin gup. theresno light on. the only tim eit comes on is when I try to drive it. its sits and idles fine, but when i go to drive it...cuts out on me until i left off the gas..
Click to expand...

Light doesn't need to be on. This isn't OBD 2 where any code trips the light. With obd1, only 13 of about 100 codes trip the light.
 
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