Idle Problems.. new thread for problems
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Small vacuum leaks may not show much change using a vacuum gauge. The range of "good readings" varies so much
from engine to engine that it may be difficult to detect small leaks. My engine pulls about 16.5" of vacuum at 650-750
RPM, which I consider rather low. It is a mass market remanufactured rebuild, so no telling what kind of camshaft it has.
Average readings seem to run 16"-18" inches at idle and 18"-21" at 1000 RPM. The only sure comparison is a reading
taken when your car was performing at its best through all the RPM ranges and what it is doing now.
Use a squirt can of motor oil to squirt around the mating surfaces of the manifold & TB. The oil will be sucked into the leaking area and the engine will change speed. Avoid using flammable substitutes for the oil such as propane or throttle body cleaner. Fire is an excellent hair removal agent and no eyebrows is not cool...
from engine to engine that it may be difficult to detect small leaks. My engine pulls about 16.5" of vacuum at 650-750
RPM, which I consider rather low. It is a mass market remanufactured rebuild, so no telling what kind of camshaft it has.
Average readings seem to run 16"-18" inches at idle and 18"-21" at 1000 RPM. The only sure comparison is a reading
taken when your car was performing at its best through all the RPM ranges and what it is doing now.
Use a squirt can of motor oil to squirt around the mating surfaces of the manifold & TB. The oil will be sucked into the leaking area and the engine will change speed. Avoid using flammable substitutes for the oil such as propane or throttle body cleaner. Fire is an excellent hair removal agent and no eyebrows is not cool...
Inspect every inch of vacuum hose there is in the car. That includes under the dash where it connects to the HVAC controls. Check the PVC hose and grommet. Remove the upper intake and check the gasket and manifold surfaces. Check the torque on the lower intake manifold bolts. Use a shop manual to get the odd bolt pattern and torque values.
Diagram courtesy of Tmoss & Stang&2birds
See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.
Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif
Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif
Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif
Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg
HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif
TFI module differences & pinout
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif
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I think Jrichker will tell ya that sounds like a worn-out TPS.
(NOte I didnt read this thread again). I was amused with all the deleted posts though.
Good luck Nick.
Ok well just got a Well's Auto Zone TPS Sensor. it is still doing it. it sticks at like 2,200 rpm and most of the time i have to turn the car off and back on to make it stop but every once and a while it will go back to normal by itself after a minute or two.
I'm out of ideas and it making me go crazy cause it is doing it now more then ever.
Other then that when it doesnt stick, its idling pretty good. not running rich or rough anymore.
please help with anything... i cant figure it out for the life of me and its making me not even wanna drive it.
When it was sticking i unplugged TPS sensor and it went back to normal idle, dont know if that helps at all.
I'm out of ideas and it making me go crazy cause it is doing it now more then ever.
Other then that when it doesnt stick, its idling pretty good. not running rich or rough anymore.
please help with anything... i cant figure it out for the life of me and its making me not even wanna drive it.
When it was sticking i unplugged TPS sensor and it went back to normal idle, dont know if that helps at all.
You still have TPS circuit problems - either a bad TPS (try a OEM Ford sensor from Ford) or bad wiring/bad connections. Dump the codes and see what you get.
Ok thanks for the reply,
ive tried 3 different TPS Sensors, the brand new one, a bbk one that came with my 70mm throttle body i used to have on and an original oem one that came on my car.
my check engine light doesnt come on at all anymore since i changed out my fuel injector harness, but im gonna try to dump codes today and see what i get.
I also dont know what other connection or wiring problems i could have.
Let me know if this is right, Considering when it happens i can turn the car off and then on and it idles fine that means it something electrical correct?
Yes, the problem is electrical. Try measuring the TPS voltages when it is acting up.
What cam are you using? I had a fox body that I ran a B cam (.480), 1.7 rollers and a 75MM BBk with a Pro M and always had a searching idle issue. I was changed everything and ended up drilling a 1/8 or so hole in the blade of the throttle body (top half of the blade) to allow a little more air to flow and supplement the IAC. It was scary but it worked.
I also have an old MGB that has 2 SU carbs. They have little spring loaded valves in the blades that do the same thing that the hole I drilled did
I also have an old MGB that has 2 SU carbs. They have little spring loaded valves in the blades that do the same thing that the hole I drilled did
I've sorted through all three pages and gone about as blind as you feel probably.
1) the last line in your quote above... What happens to make you cut the car off and then on?
Initially I thought it would idle fine and then you start it on a hot start and it wouldn't.
2) To clear that up, I need to know two things after the engine is warmed up and ready to roll. IN particular....
....A) within 30 seconds to 1 minute of cranking, how does it idle
....B) after 30 seconds to 1 minute does it idle any better or worse?
Which idle is better, A or B?
Something for you to know. I'm trying to determine if your idle is good or bad in OPEN LOOP or CLOSED LOOP. To keep it simple tell me a or b above.
Patrick.
Answer is B. it idles better after 30 seconds to 1 minute after start-up..
The reason i turn the car off and then on because most of the time it keeps sticking at 2,000rpm until i turn the car off and then on and then it idles normal again until it sticks again..
I just pulled codes, I got 11,63,34
34
PFE or EVP circuit above the closed limit of 0.67 volts.
PFE or EVP circuit has intermittently failed above the closed limit of 0.67 volts.
63
TPS circuit below minimum 0.6 volts.
TPS circuit has intermittently failed below minimum 0.6 volts.
http://www.fordfuelinjection.com/index.php?p=35
Take a look at that link. If your EGR is cracked open, or leaking air that is why your car is acting crazy on idle along with the TPS problem.
This tells me it is idling better in closed loop. It also tells me your MAF transfer is close enough so that adaptive can control your AFR and hold an idle. BUT OL (open loop) is where the problem is and it can't compensate for your errors.
Do you know how to correct these errors?
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