turnski

Ok well all else is dialed in now, butr I still have a miss and eratic idel issue till 2000 RPm that wont go away.. Ive checked TPS, and codes, and vacuum leaks, This motor has 5 miles on it . so where else sholud I look ?

AGreen

iTrader: (11)

5 miles on a professional rebuild, or self rebuild? You should check compression, but grounds can cause similar problems too. You should add a few ground wires from the block to the body & battery just for posterity's sake anyways.

turnski

Professional rebuild, Rotary Performance actually. I'm going to do a compression check on it this comming weekend since . My hours at work will be long.

calpatriot

Did you get a chance to check the O2 voltage and or green lamp in the rpm range where you are having trouble?

If they show a lean condition, it probably is not a compression problem... but I am not suggesting that you avoid checking the compression anyway...

turnski

I did check 02 sensor voltage through the range, I think as I remember it was around .356 at idle and switched to .789 to .823 at cruise. But when I do the power balance test at idle it appears as though that the rear rotor is not contributing to much at all to the idle, but it feels like it begins at 2000 rpm. when I fire it up cold it runs at 2000 and smoothly with the occasional rpm drop. Those firures are guesses because i did this saturday and dont remember what exactly they were.

calpatriot

The mixture should be rich (greater than 0.45 at idle); at cruise (steady rpm), it should be switching back and forth between rich (more than .45) and lean (less than .45)

Assuming all these were taken at operating temp, it indicates that your mixture is way too lean at idle, and that the ECU is not going into closed loop mode at cruise.

The former suggests too much air and or too little fuel at idle. This could be due to a vacuum leak, clogged injector, low fuel pressure, misset idle mixture, tps, MAF, boost sensor, air pressure sensor.

The latter suggests that there is something wrong with the feedback loop between the ECU and the oxygen sensor. This could be due to a bad sensor, bad wiring between the sensor and the ECU, bad ECU, bad temperature sensor, or bad wiring to the temp sensor. If the temp sensor never reports to the ECU that the car has reached operating temp, it will never go into closed loop mode, you will run rich all the time, which will foul the plugs and maybe do in your cat and O2 sensor.

Are you showing a code 5 on the test connector?

I think these may be from two separate problems.

calpatriot

OK, just went out for a little test drive with my test harnesses hooked up... here are the results I obtained:

O2 voltage from start to operating temperature ramped up from about 0.02 volts right after start to about .68 to .72 volts after 7 min or so. The green lamp comes on at .45v.

After warm up:
Idle: 0.68 to 0.72 volts
Acceleration: 0.68 to 0.78 volts
Steady cruise: toggling back and forth between 0.2 and 0.7 volts
Deceleration: -0.14 to -0.2 volts

When you tested the O2 voltage at 'cruise', was that in the garage, in neutral, at cruise rpm, or was it actually cruising on the road? The ECU senses if you are not in gear with the clutch out, and it stays in open loop.

SecondGenPat

I had a slight miss at idle, turned out to be dying ignition coils. After I swapped those out the idle smoothed out.

turnski

I will check that, First of because even during high rpm opopation I can feel it
miss just a little, with that
being said i think it's switching off the O2 , and its leaning itself out, I need to check to see
if it's acutualy going into closed loop op. so I'm going to check t-stat Op, that check the coolant temp sensor, I have an extra from the vert I can throw in If I have to for test purposes. Anything else I should check while i'm in there ?

HAILERS

Fully warm up the engine. Idle the engine. Turn the variable resistor slowly all the way clockwise and listen for the difference. You need to post what series car you have when posting so others won't have to SEARCH thru your previous post to figure out what series car you have.

turnski

S4 thanks for the tip. and have tried that with the idle mixture. I have to get the thing to idle first. i was just out checking O2 voltage readings, and am now about to go make a code checker. I think the T-stat may be not fully functional .

HAILERS

The variable resistor would only effect idle i.e. 750 rpms give or take. So what is your *idle* speed right now with a fully hot engine?

turnski

It wont " Idle" it lathargicaly act's/try to idle around 800 rpm . I have an idle issue that I've been batteling since I've installed the new engine..

turnski

Ok I finaly went out a re ran the readings on my O2 sensor and here's what my Fluke 87 came up with.

Funky Idle 188-.085
2000 RPM .786-865 Steady

No Rpm change from cisconnecting the BAC
No RPM change from disconnecting the Coolant Temp Sensor.

Next step is to construct diag checker and see what I've got going on . what do you think ?

calpatriot

The O2 readings at 'funky idle' are difficult to understand. Is 188 intended to be 0.188 volts? Do you really mean .085 volts at 'funky idle'?

Anything below .45 at idle is likely to be a problem, indicating an excessively lean mixture. Mine runs about .7 volts at idle once fully warmed up. Your 2000 rpm number actually seems a bit high (rich).

Your idle numbers, if I read them correctly, indicate a very lean mixture at idle. This could be due to a vacuum leak, clogged injectors, malfunctioning primary injector, bad/intermittent wiring to a primary injector, or ?

Certainly make the code checker, pull codes, and check for closed loop operation at steady 2000 rpm (you will have to do it on the road, or by disconnecting the TPS and neutral switch connectors).

If your car is not going into closed loop, the running rich all the time can foul the plugs and take out the O2 sensor.

turnski

Well I'm going t complete the code checker today.

Ok todays advanture wasnt what I was after. A short drive turned into a long walk back home and a tow. Around 40 mph she lost all ignition power and died good thing these things have relatively good glide paths.

Now it's blowing the 30 Amp EGI fuse under the hood so I will now have to diagnose that, and get back to where I was to begin with.

turnski

so with the loss of EGI Comp fuse under the hood, there were no codes stored, so what is my next move, i'm almost thinking that I have to send this thing to some one who does these every day, it's not something I really want to do But I might have to resort to it.