OK just went for a nice 30min drive( a hard drive)
Well the temp gauge on dash never made it to half way ever.

then i got home and let the truck idle for 10 min the gauge didn't change at all



just kinda stayed in this area once the truck was warmed up no matter what i did.

also i noticed when it was cold and i started to drive off i could here water trickling in to the heater core and hose under the dash. i have not had to top off the coolant at all so i am not losing any. must be some air trapped in the system. once the truck warmed up the sound went away.

So is the truck intended to be warmer at idle or at driving speeds?

So what i think i want is to find a shop with a gas analyzer that can tell me whats going on when i fix/change stuff.

Try replacing the thermostat, its possible that yours is bad or even the wrong temperature.

Nope it a stock t stat and its working..

So i went to test the voltage on my O2 and look what i found under my seat. Not too sure when this happened.




OK with that fixed i started looking at other things. I looked at asv air injection system
According to the manual it says it should only open
A: when the engine is still cold below 95 degrees
B: when warm wen you let off the gas it opens op for a few seconds.

so that all checked out

checked the tps impedance it all looked happy

set the timing to 8

the idle rps are 800

tested the impedance at the Airflow meter it was all good

I have a few questions about the dashpot thing on the throttle body. the under hood sticker says "dashpot speed 2000 rpm" now from what i read int manual it says to cover the small hole on the inside of the thing and adjust the throttle stop till 2000 rps then uncover the hole on the dashpot and the motor should slowly go back idle. Yea right freaking right no matter how low i set the dashpot speed it hangs up and hold the idle up just higher then the set idle. if i slap the gas a few times or i pull up on the gas peddle can get it to drop back! so bad dash pot maybe ? but that wouldn't mess up my smog test results by that much having the idle up may 50 to 100 rpm? any way i adjusted the set stop to not really touch the broken dashpot. so i should get a constant idle speed. holy long winded post sorry about that i

My '90 3.0 didn't want to pass smog this year either for the first time in the 17yrs I have owned it, and it was also only failing at idle. It had less than 12k on it at the first test this year since I completely rebuilt the top end, replaced the O2, cat, and it did pass the '05 smog test fine a year after the rebuild. I also had a few loose header bolts, exhaust leaks and the egr valve copper tube's crush sleave never seated, the nut was to long. I fixed all of the leake and replaced the cat after the second failed test(fortunately my tech doesn't run it through until it is done). I told the tech everything that I had replaced/cleaned/checked for working and he said there wasn't much else to look at, and at idle it was still running rich, he bumnped the idle rpm up to 1050 and it dropped the HC's to under 90, still very high compared to past tests but enough to get it to pass.

I run a second temp gauge(sensor is between the t-stat and the rad), out going water at idle is 210*, which should be warm enough for the engine to be at running temps, I also have an e-fan, but it runs all the time, so I doubt yours turning on and off is enough to cool down the engine too much. Th only thing I haven't checked that I thought of after the test was the cold start injector. I thought maybe it could be leaking fuel into the engine all the time causing it to run rich, asked the service counter at the dealer and they had no clue, said bring it and we will look at it.

I believe that Davepet a member here is a smog tech, shoot him an email and see what he has to offer.

Put your timing back where it was and check your fuel pressure and fuel pressure regulator.Then check your injectors, ones probably got a little drip.Is your O2 sensor working?Two speed idle is the easiest to pass.I though Kalifornia was tough on emmissions?

Everyone missed a key component...

You replaced your plugs with Bosch.

Yank that crap outta there and go get some Denso's or NGK's.

Pulled out the Bosch plugs, pulled the napa brand plug wires. went to Toyota got factory plugs and wires. also tested the fuel pressure it was all good. so I am going to drive it this week and probably get it tested again on thursday. I will let ya all know how it goes

i didnt miss anything.H/c levels dont have a dang thing to do with spark plug brands.The engine is running rich at idle,plain and simple.If an injector seal was bad you would more than likely have a constant lean miss that wouldnt go away at 2500 rpm.The fuel pressure regulator diaphragm failure seems most probabable.Fuel pressure would be high at idle causing increased h/c,but when engine rpms increased the engine would be using the increased fuel pressure.Just my .02.P/s,splitfire sf6d is the money plug for my 22re.