engine miss under 4KRPM

[xpnsiv93]

i've tried the swapping of MAF's and the car still seems to like the C&L 73 better than the stock one....no matter what i do/done theres an engine miss under 4K....it seems to happen right around 3K i've swapped MAF's...checked vacuums....checked plugs(all OK) and all NEW WIRESand plugs DUH!!! if i try to give the car **** and accell rapidly it misses more than once...but under normal accell there only seems to be one miss than it goes away...it happens under load i've noticed...like in 3rd-5th?? this one's got me stumped...O the codes..only 116 w/KOEO...and the normal one tellin u about the LPM...5 sumpin..dont remember...any ideas??? thanx

 

[SHO--ripper]

Are you missing any of the grounding bolts for the intake?

 

[shobikes]

I have the same thing going on - mine's '89, but I have stored koeo code 14, so I'm replacing CPS (PIP) sensor.

Check your DIS ground bolts, and those connections. What kind of wires did you get? I had misses with NAPA/Echlin, Borg-Warner, and some other cheap wires. I went back to Motorcraft, but switching to Taylors soon as they get here.

Good luck - maybe it's just Mars in retrograde...and it will all clear up once the planets align!

 

[xpnsiv93]

I went through and checked all the grounds...took DIS off and put on my NEW one off the old intake.....their AC DELCO wires..i ordered Taylor but didn't recieve them and got refunded!!...would the CTS cause this?...i've also noticed that it seems to be runnin rich...you can smell the gas whenever you open the hood and work around the engine....**** i dunno....thanx guys..anyone else wanna stab at it?

 

[SHO--ripper]

I wouldn't go replacing your CPS unless you're SURE that's the problem. It isn't a good time. Does you car stall (shobikes)?
x how old are your O2 sensors?

 

[xpnsiv93]

02's and "Y" pipe are no more than 1.5yrs old..that was a rip-off $1K i ever spent..but i was clueless about SHOforum then and will make wiser choices now.....i've read about the coolant temp. sensor goin bad..and i've got one to put in...but not sure WHAT issues that sensor goin bad will cause?!

 

[shosleeper]

sounds like a fuel delivery problem. This could cause a rich condition miss, which would clean up later in the power band, because the engine can use the extra fuel. Also if it quits around 4K it may be that the secondarys opening up lean out the mixture. Look for problems with the fuel pressure regulator and or leaking injectors. Best way to isolate is to get an exhaust gas analysis done, the HC's will give an indication where to look. It could be the CTS (coolant temp sensor) but ford's are "suposed" to substitute a known good value when one goes bad. So it will make it run rich, but not so rich that it would miss.
Good luck with you diagnosis

 

[xpnsiv93]

SHOSLEEPER>>> thanx...and to the other two(i forgot the names ) I was thinkin fuel pump...im not sure on the fuel pressure regulator is it a cheap/easy part to replace??...and the area w/in the injectors was nice and clean while doin the 60K, almost looked like new, but w/Fords u never know...thanx again..O and if u could help me w/that fuel pressure thing..thanx!!