On Mar 20, 7:12 pm, Tegger > wrote:
> "dcip" > wrote in news:1174327689.729480.32230
> @l77g2000hsb.googlegroups.com:
>
> > I have 93 accord 10th anniversary addition 179k. The check engine
> > light came on and the D4 started blinking at the same time. Checked
> > the codes and came back with a 6 for the check engine light and 1 for
> > the D4 light. Looked up the engine light code and it says that it is
> > the coolent temperature switch.
>
> It just means the ECU is not receiving a valid signal from the switch. This
> could mean anything from broken wires to corrosion to a bad switch.
>
> > I cannot find what the code is for the
> > D4. In addition, recently the idle has been intermittenly high after
> > driving and then putting it into park. goes up to about 2k and
> > sometimes surges. Sometimes it goes back down to normal (800rpm) and
> > sometimes it does not. I did clean the IAC screen and checked the
> > coolent level. I have also searched this news group about the D4 light
> > but did not find any clear info. Any input would be appreciated.
>
> The TCM code 1 can be set by fluctuating idle.
>
> Both these codes can be the result of low coolant. If you've checked the
> coolant at the RAD and found it OK, you may have a Fast Idle Thermo Valve
> that's sticking open.
>
> With the engine fully warm and the idle cycling, remove the air cleaner
> hose from the throttle body and check the LOWER port in the throttle body
> with your finger. If there is suction, and the idle settles down when you
> cover the port, the FITV is sticking open. This usally happens when the
> cooling system has been neglected.
>
> --
> Tegger
>
> The Unofficial Honda/Acura FAQwww.tegger.com/hondafaq/


Thanks Tegger. I will check it. I recently put in one of those hi-
flow air filters which you spray oil on them to trap dirt. Maybe
sprayed too much?