p0505 code, terrible idle.

[deuceforty]

So my car developed this random idle stumble out of nowhere. When cold it will idle fine, however it will have this stumble as it warms up where it seems like its switching maps on the ECU.

After this stumble, anytime the clutch is depressed while driving the car will either a.die or b.almost die.

im getting a constant CEL (cannot clear) for p0505 (idle malfunction) i will also get codes for p1400 (i have no egr systems though.) and rear o2 sensor.

I changed the IACV system with the one off my old engine, and now it seems the problem is compounded. I pulled the IACV harness and ran through all the wiring to make sure there were no cuts or corrosion and couldnt find any issues.

its at the point right now where i cant get to a stop because i have to give it gas or else it dies.

After the car is warm if i shut it off and leave it alone for a few minutes and try to start it back up it will get to 700rpms then shudder and die. It wont start afterwards unless the throttle pedal is held down all the way and i rev it a bit.

ever since i put the new IACV in it will do this even on cold starts now.

last night was a nightmare to drive, when i got home it idled at 800 with little variation as if nothing was wrong, however i put it in neutral, revved to 2k and let off the throttle. the car immediately died.

With the IACV harness totally unplugged the car will not die after load is put on the engine, and i was able to drive the entire time without any idle issues at all. the idle was very high, but this can be expectted from not having any systems in place.

what in the WORLD is wrong with my car?

[deuceforty]

bump?

[dlydrvn240]

Is this an OBDII car or is it an OBDI...i see its a 95 so wasnt sure what you ended up with. If it is a OBDII did you put a 100K ohm (1/4 watt) resistor plugged into the EGR temp sensor connector (100k ohm should be brown black yellow then a gold or silver or no stripe for tolerance level).

When i removed my EGR i had similar issues with the idle dropping and peaking and whatnot before getting the resistor (at Radioshack).

Thats about all i have to offer...if nothing else its a free bump.

[deuceforty]

Is this an OBDII car or is it an OBDI...i see its a 95 so wasnt sure what you ended up with. If it is a OBDII did you put a 100K ohm (1/4 watt) resistor plugged into the EGR temp sensor connector (100k ohm should be brown black yellow then a gold or silver or no stripe for tolerance level).

When i removed my EGR i had similar issues with the idle dropping and peaking and whatnot before getting the resistor (at Radioshack).

Thats about all i have to offer...if nothing else its a free bump.

its an OBD1 system.

very interesting point you made... i had a resistor in the EGR plug but kept getting the p1400 EGR engine code. I took it out to see if it made a difference. I do not remember when i did this however... but it did the slight stumbling before i pulled the resistor.

im very tempted to pull all of the idle air equiptment and just put block off plates and use the throttle body to control idle.

a friend of mine suggested i check the TPS... could this be an issue?

[deuceforty]

since a few members said it was blowing out fuel on cold starts i pulled the rail and FPR and took it inside for inspection.

all of the lower seals were dry except for cylinder #4 next to the FPR, the lower seal was wet, so i pulled that injector out to examine the o-rings.

the upper o-ring looked like it had a small piece of sand or something on the side, so i took it off and im going to clean the inside of the rail and apply more white lithium grease to both upper and lower injectors upon install.

i also have a new OEM replacement FPR, but the o-ring supplied with it seems to be slightly too big to fit in my rail... should i try and take the old o-ring off my old fpr and try and put it on the new one?