Tried to set base ignition timing and surging

[Natedog]

Tried to set my base ignition timing tonight. Adjusted my TPS so that it is at 0.855 volts KOEO throttle closed, disconnected battery positive, reconnected and fired right up as usual. It has not wanted to idle below 1200 rpm in neutral with my new m5r1 4x4 (was a4ld and 4x2) and the tach seems to kinda jump up and down occasionally EDIT: 50 rpm.

Got it warmed up, checked the timing and it was at 30*BTDC, pulled the spout plug to check base timing and it's at 10* BTDC but is surges and won't stop until I plugged the spout connect back in. Any suggestions?

EDIT: Driving it to work this morning and will pull codes this evening and post what I find.

FYI, pulled spark plugs the other night and they look pretty good.

[Natedog]

Just pulled codes and this is what I got.

KOEO: 89 and 11

KOER: 12 and 13

89.....I think is the Lockup solenoid (LUS) circuit failure is because of my a4ld to m5r1 swap. I hooked up the neutral saftey switch wires and figured out the reverse light wires (but haven't hooked them up yet), the rest of the wires are still bundled up and waiting to cut them out of the harness. 89 could also be Converter Clutch Override (CCO) solenoid - circuit failure OR Exhaust Heat Control (EHC) solenoid - circuit failure....don't know which but assume prolly the lockup solenoid and/or converter clutch.

As far as the 12 and 13 go....12 can't raise engine speed above normal idle....it's idling at 1200 to 1300 RPM! 13....RPM out of spec during normal idle operation OR D.C. motor does not follow dashpot.

During this whole test my timing was at 30* BTDC and at one point went off the scale....maybe 44* BTDC (just guessing as it was off the scale on the harmonic balancer.)

Any suggestions?

EDIT: After all the tests I unplugged the EGR vacuum line at the right side upper intake manifold and plugged it with a cap, re-started the engine and it still idled high...around 1200 to 1300 RPM. Had thought maybe a vacuum leak in the cheesy hard vacuum line that breaks easy now that it is old and brittle.

[Psychopete]

KOER: 12 and 13

I first thought vacuum leak, you might spray around your engine to make sure this is not the issue. Do you have any popping/slight backfiring at idle?

I think 12 and 13 are basically indicating that it's probably having issues getting a sane signal from the IAC.

12 - Idle Speed Control motor or Air Bypass not controlling idle properly (generally idle too low) - ISC

13 - Idle Speed Control motor or Air Bypass not controlling idle properly (generally idle too high)

http://www.therangerstation.com/tech_library/2digitcodes.html

I know you can't tell me that you don't have a spare IAC lying around :). I wouldn't overlook the wiring/plug/etc though.

IMO, your base idle voltage seems low. I try to get 850RPM w/ A4LD @ ~.98 volts. Manual could be different, never owned one.

Pete

[Natedog]

Yeah, I thought maybe vacuum leak too...that's why I tried blocking off the EGR vacuum, system with no change in idle speed. No popping/slight backfiring at idle either.

I got my code definitions from the Actron reader book that came with the reader.

I kinda wondered if IAC was dirty, I have a spare that looked dirtier inside that I will clean with carb cleaner and swap on to see if it changes anything.

Wiring and plug looked good, but I'll look at it again, maybe dirty contacts on the plug or something.

I tried for lower end of voltage range thinking that would give me lower RPMs at idle. A4ld is gone, M5R1 manual now.

What about my left over a4ld wiring and the 89 causing other problems?

[Psychopete]

A4ld is gone, M5R1 manual now.

Manual could be different, never owned one.

I was aware :). I just saying that I don't know what the ball park base idle is for a manual. I do know the base voltage should be around .98. I read somewhere (Wickedsludge?) that the PCM stores the base voltages of sensors, using that figure on the assumption that the sensor is good. You might drain the PCM after readjusting the TPS and swapping IACs.


What about my left over a4ld wiring and the 89 causing other problems?

Not that I can think of off hand. It's suppose to work, in theory, but I've never tried an auto PCM w/ a manual truck.

Pete

[Natedog]

NP and thanks, just checking. :) I removed positive battery cable after setting the TPS.

EDIT: On cold starts it starts fine and revs to about 2000 RPM and then as it idles down it kinda stumbles and almost dies (sometimes does but starts right back up) however the idle never goes below 1200 RPM.

[Natedog]

Replaced the IAC with a spare I had and soaked it in carb cleaner first.

Gahh! Broke one of the dang plastic vacuum lines for the EGR and in the process of fixing it, I broke the other one! Is there a good solution for replacing these brittle old pos vacuum lines?

After installing my spare IAC it still starts fine and idles up to 2200 RPM for a couple seconds, then down to 2000 RPM for about a minute, then down to 1200 for about ten seconds, then it tries to go down to 800 RPMs and sputters and revs back up to 2200 RPM, then after a couple seconds it goes down to 1200 RPM and then after about ten seconds it goes down to 800 RPM sputters almost dies and revs back up to 2200 RPM.....it'll do this over and over if you let it idle.

Thinking about cleaning the spare IAC a little more....what should I try?

[Natedog]

Adjusted the TPS up to 0.984 volts tonight and now it idles up to 3000 RPM when first started and then settles down at 2200 RPM after twenty seconds or so. At full open throttle I get 4.64 volts on the TPS and the power wire has 4.97 volts KOEO. Sprayed the crap out of the IAC with Berryman's carb cleaner (good stuff) via the inlet in the throttle body just upstream of the butterfly valve and it didn't seem to make much difference....this is after soaking the valve for a half hour last night and swapping valves with my spare used one off my other 2.9. I'm at a total loss what to do next so swapped my MAF sensor even though that didn't seem like the problem....and of course no change.

WTF???

[Natedog]

Thinking that I need a MANUAL Transmission EEC because this is getting nowhere and an a4ld idle speed is supposed to be about 800 rpm in Drive, which puts a load on the engine! Using the same computer with no load on the engine because it's in Neutral, not Drive!

Wasn't sure, but after driving it more this morning I'm pretty sure that I'm getting some pinging at medium throttle between 2000rpm to 3000rpm. When grabbing second gear it kinda jerks a little. When the engine gets down around 2000rpm while decelerating, when I ease the throttle back open a little it kinda jerks too.

[MAKG]

You will need a manual computer to pass smog. You MAY need a door post sticker as well, since you will fail smog if the idle speed is wrong, and it is different for manual transmissions. Call your smog ref; this would seem to be a no-brainer for approval.

"Hunting idle" on a manual computer means the computer doesn't know it's in neutral -- this is what the neutral sensing switch is for. You don't have to control idle if you're in gear. I don't know if there is something similar in the auto computer when the TCC is locked. There may be, and your computer can't know if the TCC is locked because it can't talk to it....

A lit check engine light is a guaranteed fail. A hunting idle is a probable fail.

As for your broken EGR lines, if it's the hard plastic green and red ones, they can be easily patched with some bulk vacuum lines. I like to seal them with a VERY light coat of black RTV (be very careful not to block the line!).

[Natedog]

Thought I'd need the computer. Will look up number for smog referee...hope they don't charge $$$....never had to use one before.

Yeah was wondering about the TCC error code and idle too.

I don't have a lit CEL. Figured hunting idle would be a problem.

Yes the hard green and red lines...this was my good un-broken set that I swapped in because my original set had so many patches. BTW, Toyota vacuum lines (metric, but don't remember the size) last a very long time and are a perfect fit over these lines.

Thanks for your input MAKG. :)

[Natedog]

Swapped in a 1988 Ranger 4x4 manual transmission EEC and it runs alot better. Drivability is very good, pinging is way less, but I still have a high idle problem....1200rpm! All I did was swap the EEC, plug the egr vacuum line at the intake manifold. I did not disconnect the knock sensor or anything else for this test.

Checked timing and it was at 24*BTDC (that seems better than 30*), pulled the spout plug to check base timing and it's at 10* BTDC with steady engine RPMs....my surging is GONE! :)

Pulled codes after driving it and....

KOEO: 95
(O) Fuel pump: open, bad ground or always on - Power / Fuel Pump Circuits
(R) AIR not Diverting (AIRD) - Air Injection
(M) Possible bad fuel pump ground or open between fuel pump and pin 8 at PCM (Fuel Pump Monitor signal) - Power / Fuel Pump Circuits


KOER: 13
(O) ISC did not respond properly (extends to touch throttle then retracts for KOEO) - ISC
(R) Idle Speed Control motor or Air Bypass not controlling idle properly (generally idle too high)
(M) ISC sticking, open ITS circuit or TP sticking
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

I've swapped between my two IACs and no change, so I think I need to replace my IAC with a new one and hopefully that fixes my idle speed too high. Then clear computer, test drive and pull codes again?

Dont' know what to think about the 95 error code.

[Natedog]

Used a dvm and checked out my IAC and wiring this morning. It seems my IAC is bad. The 1987 IAC is a different part number and the passageways down inside where the valve is look smaller than the 1988 IAC. So looks like I should go with the 1988 part for compliance test purposes. For those who've put the larger TB on their 88 and newer 2.9 how does it run and did you change the TPS or anything else when you changed the TB?

I'm going to call and make a smog referee appointment tomorrow.

[Natedog]

Replaced my IAC with a NEW one (Wells p/n TV200) for 1988 Ranger and idle is way better. Did the complete emissions swap to CA 1988 last night and now my idle is perfect at 850rpm in neutral at operating temp! :) This swap eliminates EGR and knock sensor.

[greaseyfingers]

I have a 87 4x4 ranger, model STX, with an aluminum housing 5 speed transmission, that has a square steel inspection plate that is bolted to the bottom of the tranny, with a drain pug in it's center..

I was wondering what the purpose of the switch, sensor, or whatever it is called, which has two wires attached to it, that's threaded and screws into the top of the transmission, just ahead of the 5 speed shifter mounting plate that's bolted to the transmission housing.. I think my transmission is either a mitsubishi fm145, or 146 ??

the switch, I was referring to has threads on it that goes right into the tranny, on top, just a little bit in front of the 5 speed shifter mounting plate..

the wires on mine are mine are broken off, too close to the base, and can't be reattached.. could these wires being broken off, possibly, be the cause of a 2.9 idling weird, sometimes, and a engine running erratic, besides, quite often..

does anyone know what the function of this switch, sensor, or whatever it's purpose is really for ??

I thought this sensor or switch, or whatever it is, might function as either a neutral switch, or else possibly as some kind of tranny sensing speed sensor, for providing information to the vehicle's computer, for telling it what gear the tranny is in, as it's being driven..

or could it be this switch, for whatever purpose it's function is for, could be for completing a circuit to a light, somewhere, on the dash, that's suppose to let you know when the tranny is in either 4x4, or high or low range, being my owner's manual indicates that there is a light on the dash which is suppose to indicate so..

however mine has never worked.. being the wires are broken off my tranny switch, as I described, could this be the purpose for which it was designed for ??

would like to hear from those who can provide some accurate and knowledable information..


You will need a manual computer to pass smog. You MAY need a door post sticker as well, since you will fail smog if the idle speed is wrong, and it is different for manual transmissions. Call your smog ref; this would seem to be a no-brainer for approval.

"Hunting idle" on a manual computer means the computer doesn't know it's in neutral -- this is what the neutral sensing switch is for. You don't have to control idle if you're in gear. I don't know if there is something similar in the auto computer when the TCC is locked. There may be, and your computer can't know if the TCC is locked because it can't talk to it....

A lit check engine light is a guaranteed fail. A hunting idle is a probable fail.

As for your broken EGR lines, if it's the hard plastic green and red ones, they can be easily patched with some bulk vacuum lines. I like to seal them with a VERY light coat of black RTV (be very careful not to block the line!).

[Natedog]

Greasyfingers,

Those wires on the fitting near the shifter are prolly for your reverse lights. Do your reverse lights work?

Your neutral safety switch (requires depressing the clutch pedal to crank/start the engine) is located on the top part of the clutch pedal (inside the truck cab) and is totally seperate part. Automatic transmission Rangers have a similar switch (located under the gear indicator on floor shift autos) that prevents engine crank/start in every gear except Neutral and Park. I eliminated this by iirc connecting the two wires under the dash.

[greaseyfingers]

yes, my backup lights are working..

those broken wires on this switch, sensor, or whatever it is, that is threaded and is scewed into the top of my ranger's 5 speed tranny housing, several inches inches in front of the shifter, have been like that before I bought this 87 ranger stx..

however, my owners manual says there are suppose to be indicator lights on my ranger's dash instrument panel that indicate when my 4x4 is engaged, and if it's in high or low range..

I can't reattach these wires cause they're broken off, right at point of entry into whatever this thing is..

do you think this thing might be for the dash panel indicator lights, for completing a circuit, whenever the 4x4 is engaged and if it's in high or low ranger..


Greasyfingers,

Those wires on the fitting near the shifter are prolly for your reverse lights. Do your reverse lights work?

Your neutral safety switch (requires depressing the clutch pedal to crank/start the engine) is located on the top part of the clutch pedal (inside the truck cab) and is totally seperate part. Automatic transmission Rangers have a similar switch (located under the gear indicator on floor shift autos) that prevents engine crank/start in every gear except Neutral and Park. I eliminated this by iirc connecting the two wires under the dash.

[Natedog]

yes, my backup lights are working.. ......
....do you think this thing might be for the dash panel indicator lights, for completing a circuit, whenever the 4x4 is engaged and if it's in high or low ranger..

OK and yes could be....got a picture? But the xfer shifter is on the external left side of the trans....so a pic would help.

[greaseyfingers]

no, unfortunately I don't have a pic to show, sorry..

and yes, the transfer shifter is on the external left side of the transmission, as you said, which is correct..

so, do you think that the thing, (with the broken wires), which is threaded into the center of the transmission housing, several inches in front of where the ranger's 5 speed shifter plate is bolted to the tranny, is some kind of tranny speed sensor that is suppose to be relayed to the engine's computer, or maybe a tranny neutral switch, instead of being a mechanism switch, for completing a circuit to the dash instrument counsel indicator lights that are suppose to show when the tranny's transfer case is engaged in 4x4 hi or low range..

this 87 ranger stx, 4x4, 5 speed tranny has a square steel inspection plate that's bolted to the bottom of the aluminum transmission housing, with a drain plug in the center of it.. so that would make it mitsubishi transmission, wouldn't it, if that information helps, any, for this discussion..



OK and yes could be....got a picture? But the xfer shifter is on the external left side of the trans....so a pic would help.