2ToneEM1

Having the typical idle problem everyone else is... Idles fine when its cold, then at operating temp it jumps to about 1500-2000 and surges up and down after driving it. If I just let it sit and warm up the idle never changes. And it is giving me codes for p0170, p0172, p0505. Smokes a little on start up and seems like its getting terrible gas milage.

Tryed cleaning the IACV, air in coolant, checked for vacuum leaks, the head was off recently getting 2 valves replaced, and had the valves adjusted, a 3 angle valve job was also done, has a b&m fuel pressure regulator.

B18C5-EH2

You have systeom too rich and system too lean codes (the P0170/P0172 codes) and idle control system malfunction code (P0505)

Basically you have a combination of THE shittiest codes to try and diagnose, because each code has a list of 7-8 different "possible causes" which are a PITA to check.

My first impression is that there is a problem with the valvejob and/or vacuum leak due to the head being off recently. System too rich/lean codes can be caused by improper valve adjustment, or worse, bad valvejob.

Idle air control problem can most easily be attributed to a vacuum leak since the head has been off.

Basically on a bone stock, head has never been off car, these codes are still a bitch. Add to that the other unknowns and variables that come with a head job and this isn't going to be an easy dagnose and fix IMO.

B18C5-EH2

BTW did a shop do the head work and install, etc? If they did you can bet I'd march my *** right up there and ask them what can be done about it.

If a machine shop did the valvejob and you did the teardown and reassembly well then it might prove to be difficult to find a shop willing to go back through it, or let me reword that, you may end up having to pay someone to go all the way back through the work to sort it out.

My recommendation:

Have the valves readjusted

Triple check for vacuum leaks - try spraying carb cleaner around the various orifices/gaskets at the Tb, IM, etc. and see if the idle picks up when spraying at certain areas. If the idle picks up then you've got a vacuum leak.

2ToneEM1

Yeah, a shop did it all, if I cant figure it out this weekend ill take it to them and see what he can do.

Its not saying system too lean tho, of course I may have missread the code but it says fuel trim malfunction

B18C5-EH2

Whatever you do don't go too deep in trying to diagnose/fix the issue, because if you "tamper" with it the shop can very well deny any liability and sday you must have done something trying to fix the issue.

I am telling you from a shop stand point here:

Do not try and diagnose/repair the issue - leave it alone and let them sort it out

2ToneEM1

I wont do anything like that, just try a few more small things and if no luck take it back to him. He is a friend of mine so I know he will take care of me.

bluepitbreeder06

hey did u get the problem fixed? if so what was done? mine is doing the same thing but i dont ahve anything and i didnt do anything like u just bolt ons thanks

2ToneEM1

Yeah, took it to my mechanic and he adjusted the idle screw and the screw under the throttle rotor and now it idles like it used to

bluepitbreeder06

what is the throttle rotor? the screw on the throttle body? thanks

2ToneEM1

its the thing the throttle cable pulls on to open the butterfly

4dohs4mohoes

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 2ToneEM1 &raquo;</TD></TR><TR><TD CLASS="quote">Yeah, took it to my mechanic and he adjusted the idle screw and the screw under the throttle rotor and now it idles like it used to </TD></TR></TABLE>

Hmmm. Thats kinda weird that you would have to adjust that. If the mechanic did the valve job to OEM specs, that should have to be touched.

But then again, if that fixed the problem...

2ToneEM1

Yeah but both screws were way out of adjustment for some reason