North American Turbocoupe Organization



Wht else..Idle problems...
koolone Offline
Junior Member
#1
Ok Here we go... I've been reading and searching for the same problem I'm having...88 tc auto 83,000 miles.I owned the car since it had 28,000 on it. It's well cared for. The car starts fine and idles great when cold. As soon as it warms-up like just when it's going to closed loop. The idle drops and the motor sits there at a low idle and just stumble's. I can hit the gas and after a few mins it will settle down. However it does buck every so often. Runs great out on the highway no miss. The only code I get is a 25,and 34. Both of which we know are are false trips. 1 I did not beat on the exhaust and 2 it has the recall done to it for the egr system. I have purchased many parts over the years cause I had planned to keep this car forever. Parts I swapped to try and cure.... Pip, Tfi, Egr,Injectors, cleaned the throttle plate and also complete tune up...wires cap ect. Any other idea's??? Thanks for taking the time to read thru this.
Reply

Ryan H Offline
Posting Freak
#2
What kind of wires/cap/rotor/plugs did you use?

Also what brand TFI and if used is it a known good one?

------------------
Ryan Harris

1988 TC 5 speed, all options including sunroof. Running on a destroyed block and cracked head for a couple months Big Grin
'88 TC Smile Walbro 255HP, Stinger FMIC, PIT BOV, Pro 5.0, Kirban, RR cam, FRPP strut tower brace, T3
Reply

koolone Offline
Junior Member
#3
Quote:Originally posted by Ryan H:
What kind of wires/cap/rotor/plugs did you use?

Also what brand TFI and if used is it a known good one?

Thank you for the reply...
All parts were new...All but wires were motorcraft or autolite....And the problem existed before the parts were changed...
Reply

Jeff K Offline
Administrator
#4
Did you run the KOEO test? I dont see any mention of it in your post. Does the CEL work? Has it ever come on? Have you removed and cleaned the IAC? Have you checked fuel pressure? How do you know the problem occurs at the open - closed loop transition?

------------------
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 21 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 04 Taurus Duratec (wifes car)
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 24 psi, forced air IC, water injection, BPV, Ranger cam, subframes, etc., etc.
86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP N2O, ignition, gears, suspension, etc., etc.
05 Taurus SEL Duratec daily driver
04 Taurus Duratec (wifes car)
02 Pontiac Grand Prix GT
95 Taurus GL Vulcan winter beater
67 Honda 450 Super Sport - completely customized
Reply

koolone Offline
Junior Member
#5
Quote:Originally posted by Jeff K:
Did you run the KOEO test? I dont see any mention of it in your post. Does the CEL work? Has it ever come on? Have you removed and cleaned the IAC? Have you checked fuel pressure? How do you know the problem occurs at the open - closed loop transition?

Hello Jeff and thank you for the reply......I'm so glad I found this site. You guys are geat.. Anyway. Yes I did pull the codes KOEO...25,34...yes the CEl wrks and no It never came on to indicate a problem. The fuel press wth just the key on is at 45 psi...When running it's at 34 psi. Hit the throttle and it jumps to 43 psi and then settles back down to 34 psi. As for the closed loop...it runs smooth when I first start it (cold) then as it warms up and wht seems like the t-stat opens or something it goes into that rough idle. I'm going to to ck the coolant sensor and then I'll pull the IAC and clean it.
Thanks.
Reply

Jeff K Offline
Administrator
#6
BTW, Welcome to the board!

Codes 25 and 34 are KOER (key on engine running) codes. Did you do the KOEO (key on engine off) test?

Your fuel pressure sounds a little on the high side, but within the Ford spec range.

Yes, the ECT (sticking up between injectors 2 and 3) can cause the problems you are having, and it will not always set a code unless it is really way out of range (basically open or shorted). I check a suspected bad ECT by hooking it to an ohm meter, putting it in a pan of water on the stove along with an accuate thermometer. I heat the water slowly, and see if the resistance increases with temp correctly. Be aware that if the nipple on the lower intake pointing toward the driver side fender gets plugged (common problem), coolant flow to the ECT will be restricted, causing it to send incorrect info to the EEC.

------------------
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 21 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 04 Taurus Duratec (wifes car)
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 24 psi, forced air IC, water injection, BPV, Ranger cam, subframes, etc., etc.
86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP N2O, ignition, gears, suspension, etc., etc.
05 Taurus SEL Duratec daily driver
04 Taurus Duratec (wifes car)
02 Pontiac Grand Prix GT
95 Taurus GL Vulcan winter beater
67 Honda 450 Super Sport - completely customized
Reply

koolone Offline
Junior Member
#7
Update....Pulled the IAC off and cleaned it..Did not look bad at all. Checked TPS and set it to ford spec. Started and let it warm up..Same problem..It's still idles fine cold. Just when it seems like the t-stat opens the motor gets the shakes and idle is very rough. Gona pull the temp sensor and ck it. Is ford like gm with respect to using open and closed loop? Thanks for ur time.
Reply

Jeff K Offline
Administrator
#8
PCM goes closed loop pretty quick after startup when ambient temp is 60 deg or above. Unlike many people will tell you, the water temp DOES NOT have to be at operating temp for it to go closed loop. Water temps a little over 100 deg (or even lower) will enable closed loop if IAT is high enough. PCM goes open loop over 3000 RPM, and greater than about 75% throttle.

------------------
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 21 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 04 Taurus Duratec (wifes car)
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 24 psi, forced air IC, water injection, BPV, Ranger cam, subframes, etc., etc.
86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP N2O, ignition, gears, suspension, etc., etc.
05 Taurus SEL Duratec daily driver
04 Taurus Duratec (wifes car)
02 Pontiac Grand Prix GT
95 Taurus GL Vulcan winter beater
67 Honda 450 Super Sport - completely customized
Reply

koolone Offline
Junior Member
#9
Update II...Checked the coolant sensor wth a known good thermometer. Falls within specs on the ohm meter. Now this time when it warmed-up and got the shakes I pulled the connector on the IAC...Idle dropped and the motor smoothed rt out...Plugged it back in and the rough idle returns.. I let it cool off and started it again and pulled the IAC connector wth the engine cold and no shakes. I'm not sure wht that tells me at this point?.. Thanks for reading thru this saga...
Reply

Jeff K Offline
Administrator
#10
Could be a bad IAC. Sometimes cleaning them doesnt work, as they develop other problems. Could try one from the JY (any mid 80s - early 90s Ford IAC will work), or try a new one www.rockauto.com has them for about $60.

------------------
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 21 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 04 Taurus Duratec (wifes car)
Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 24 psi, forced air IC, water injection, BPV, Ranger cam, subframes, etc., etc.
86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP N2O, ignition, gears, suspension, etc., etc.
05 Taurus SEL Duratec daily driver
04 Taurus Duratec (wifes car)
02 Pontiac Grand Prix GT
95 Taurus GL Vulcan winter beater
67 Honda 450 Super Sport - completely customized
Reply





Users browsing this thread:
1 Guest(s)



Theme © iAndrew 2018 - Software MyBB