This is topic HELP!!! in forum Tech Talk at Northern California Ford Owners  .


To visit this topic, use this URL:
https://californiafords.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=6;t=019777

---

Posted by scoop331 (Member # 8726) on :
 
I own a 93 fox it miss fires around 3500-4000 it carries rpm fine until it hits that rpm range. I swapped just everything mass air,computer,oxygen sensors,coil,spark plugs,spark plug cables,distributor,tfi modual,cap and rotor and checked timing.I changed just about everything the car sat for a year tank was emptied and has new fuel. The only thing I can think of is a dirty fuel filter. Fuel pump primes every time. Any input is appreciated just seeing if any one has had this issue.

[ April 02, 2009, 01:18 PM: Message edited by: scoop331 ]
 

---

Posted by Venomousnotch (Member # 8695) on :
 
You might wanna replace the fuel filter and check the oxygen sensors...

 

---

Posted by rollin5ive0 (Member # 8592) on :
 
oh oh oh oh very important make sure the blinker fluid and ...yup thats right betcha aint ever checked your muffler bearings hahahahaha and that was the big my one and only shoti know it's alraedy toooo late for an april fools joke \but i dint get toplay one
 

---

Posted by scoop331 (Member # 8726) on :
 

quote:

---

Originally posted by rollin5ive0:
oh oh oh oh very important make sure the blinker fluid and ...yup thats right betcha aint ever checked your muffler bearings hahahahaha and that was the big my one and only shoti know it's alraedy toooo late for an april fools joke \but i dint get toplay one

---

that must be it!
 

---

Posted by scoop331 (Member # 8726) on :
 

quote:

---

Originally posted by Venomousnotch:
You might wanna replace the fuel filter and check the oxygen sensors...

---

yea i forgot to add o2's were changed
 

---

Posted by 166 Merlot (Member # 1549) on :
 
sup scoop, what happens after 4k?
 

---

Posted by scoop331 (Member # 8726) on :
 
I let off when it happens. But it miss fires and sometimes it backfires.
 

---

Posted by 166 Merlot (Member # 1549) on :
 
start with the fuel filter bro, then if that still doesnt' work, run some fuel injector cleaner, then if that still doesnt' work, change the only two sensors u haven't changed yet, the ECT and ACT. Oh and make sure your grounds are solid, ur battery isn't in the trunk is it?
 

---

Posted by F.or O.nly R.eal D.rivers (Member # 8971) on :
 
You dont have a fuel pressure guage,the pump can still be working but not providing enough fuel pressure at that rpm?
 

---

Posted by scoop331 (Member # 8726) on :
 
yea im going to check that today because i swapped the filter and it feels better now it does it right before 5000rpm.
 

---

Posted by Adam5.0 (Member # 6995) on :
 
i would check the coil and get a scope on the tps and look for any dead spots.
 

---

Posted by scoop331 (Member # 8726) on :
 
coil should be good its new. i already checked the tps and it was good. im going to check fuel pressure today

[ April 04, 2009, 03:47 PM: Message edited by: scoop331 ]
 

---

Posted by asskickn88 (Member # 4957) on :
 
If you've got bad valve springs that could happen as well. The valves start floating, it backfires and misses. Are you running an aftermarket cam, rockers, high mileage on the heads or anything along those lines?
 

---

Posted by scoop331 (Member # 8726) on :
 
Car is stock, millage isn't to high its at 109,xxx.
 

---