Running Rich

[Alibi]

I'm getting hard starts sometimes... I have to crank on it a few seconds to make it start up. I did swap the FPR from my other car and that did help the starts some but there is still some cranking involved. I also checked my fuel pressure (with a bad gauge which I have since replaced but haven't checked again) and got around 35 PSI so I'm currently thinking that I may have a dying fuel pump.

But... I just need to time to swap in the fuel filter and FPR though. That probably won't happen till next weekend.

...and I'm fairly certain theres not a MAP sensor but I've been wrong before.

[dirtracr95]

yea theres no MAP i was getting mixed up with other cars i was working on at school. they really try to cram tons of information into your head here at wyotech

[Alibi]

Time to revisit this thread.

I replaced the FPR with a new one and the idle seemed to get a little better but no increase in fuel economy.

Next, I replaced my IAC valve with a new AC Delco unit from RockAuto. When I pulled the old one I found out that the gasket was too far down but I think it would have still sealed. Most notable was the pintle was much further out than the new one. Here is a picture to compare (sorry, cell phone pic ):



Now the idle is a little bit better again. I haven't driven the car enough to tell just how much better but my idle seems about 50-100 RPM higher. It used to stay right around 500 RPM and it would fluctuate just a little but now it sits just a little above the 500 mark on my dash.

I still need to install my fuel filter and check the fuel pressure again though... I just hate changing the filter because fuel makes my skin feel really gross :(

So, any thoughts on just how much the old IAC could have messed with my engine? Could a bad IAC cause poor fuel economy at higher RPMs?

[Alibi]

Fudge... now I've got a code 39 - Torque Converter Clutch Circuit

I had this on my last transmission but when I got the new correctly geared (and non-slipping) I went ahead and replaced the TCC solenoid with one I had bought. So... if this transmission is throwing the code for it, then maybe I just had a bad wire in the first place?

I'm running around 2000 RPM at 60MPH and around 2500RPM between 75 and 80 MPH.

Thoughts, anyone?

[Jrs3800]

Well with the same 2.97 Ratio I run exactly what you stated... Right about 2500 at 72-80, but the tac is a wee bit off.. I'll almost bet yours is too.. So now the question is... What does a Scantool show for Engine RPM, Vehicle Speed when the TCC is commanded on..?

This may be one of the issues with your lower mileage.. But even without TCC lock you should do better than 21-22 on the open road..

[Alibi]

I found something else of interest today though! I decided to run a bit of Seafoam through my booster vac line and when I did I got a rather impressive plume of smoke coming out of the base of the EGR valve. Not at the gasket surface, but at the base of the valve where it connects to the 3 subvalves.

So... this would explain the sulphur smell that I get when I accelerate hard methinks but would it also explain my crappy fuel economy?

[Alibi]

Ok, I got some bugs worked out today.

First I installed my new to me EGR valve. The old one had a screw sheared off which was allowing it to leak.

Second, I tried to test my TCC solenoid by grounding pin D. The pins are listed on the electrical harness but when I tried grounding it I didn't hear it click so I may have a bad solenoid (gaaaaahh!!). Or I just didn't hear it click because I don't hear very well... Or... I could be doing it wrong and just have a bad harness which I can steal from my Bonnie parts car. Would it be worth it to splice in a different harness just for the heck of it? I need to try the same thing on my '88 to see if I can hear it click so that I could at least confirm that I'm doing it right (its battery is dead at the moment though)

Next, I decided to check the voltage at my TPS. When I started poking around it I discovered that one of the clamps for the PCV exhuast hose was loose and that the TPS was missing a set screw. I checked the voltage and it was at .466 (desired range is .33-.46 so it was a tad high) but then I tried to wiggle it and I got the value to change since it was missing a screw. So... I set it to .40 volts and put another screw in it from an extra sensor I had laying around. The one issue I am having is that its supposed to be at about 5 volts at WOT but on mine it only went up to 4.15 V ... does that mean the TPS is bad? In which case I could go ahead and swap in the new one I have anyway.

So... I started the car up and my idle is about 900 in park and then in gear its about 700-800 (high end of correct idle speed, I suspect it would go down once the engine reaches operating temps). The idle is definately smoother with the non-wiggling TPS, clamped down PCV line, and new EGR but just how much better it does on the road is yet to be determined.

Could any of this stuff have helped my TCC issue though? I know the TCC won't engage if it senses that the engine speed is different than the transmission speed.