I just read all through all this...well I gave it a good skim. Check all grounds and power leads to the motor. A bad ground will have the tac going nuts. I had a neg come off the battery on a 78 280Z and the tach went crazy.

On the fuel side of this...they keep changing the mixture of the gas especially in winter. My Lincoln pings a bit on me when taxing the engine. Like going up a steep hill in a high gear once it down shifts it's fine. I usually run a bottle of Lucas injector/fuel treatment through it every other tank. I use this in all my cars, I get it by the gallon. The stuff is good.

Ok trans, as far as I know all newer vehicles the TC will lockup and I believe on the older ones they will as well. I have not come across an auto that does not lock. You get much less wear and tear on the tranny fluid if you can run and keep it locked. It should be able to lock in 3rd and 4th. Mine will lock in 3,4,and 5. Depending on how your driving they typically will not lock until high gear. I'm not an expert on auto trans, just my thoughts.

For the lights and tach check the alt output as well.

/

 

I think I might have fixed the tach issue. When I redid my corner lights to clear corners, somewhere along the line, I crossed a turn signal wire and a parking lamp wire. Noticed it when the one side halo wasn't coming on (these are tapped into the parking light). Only when the turn signal was on it would flash with the turns. Fixed that and it hasn't seemed to have acted up. Weird I know. But.... can't argue with the results so far. lol.

From what I have researched, this thing definitely has a lockup trans. And I have counted all 3 shifts (1-2, 2-3, 3-4) plus the lockup "5th gear" shift. So this is locking up as far as I can tell. So no more trans worries. (for now)

Since the dizzy cap and rotor change, the engine is much happier, however the hesitation is still there, but not nearly as bad as it was. Almost not noticeable if you didn't know it was there before.

 

I know you have an E34 but you might check out e30tech.com im on there constantly with my questions the people on there are very knowledge able, of course you'll have to post in the off topic section.

good luck! i had an E28 that broke a wire within the harness and it went completely nuts, but here in AZ these beemers run extremely hot (dont know if thats the case with a 92/your locale) and just bake wires. just a thought, its no fun taking out the loom though, make sure you know where everything plugs into and be careful with all those plastic connectors.

 

Hesitation, Pinging tells me lean. TCC lockup is dependent on TPS, VSS, MAP/MAF, and ECT. ECT has a lot to do with open and closed loop fuel trims. check your ECT resistances. According to AllData;

RESISTANCE TEST


@ 68°F 2.2 K - 2.7 K ohms

@ 176°F 290 - 360 ohms

 

ECT is brand new. Better not be bad. That was replaced when I replaced everything cooling system related after we bought the car. But will check out.

 

Just for my future reference.

BMW E34 535i Cylinder Head Gasket Set 1988-1993 (OEM) $180.94 shipped UPS Ground

http://www.fcpgroton.com/product-exe...1993+%28OEM%29

 

Hey there xtreme22.

"I know alot of us have BMW's on here. I know it's a long shot, but IF you have any experience with the e34 or 4hp22 trans, by all means please chime in here."

True that; I hate the bmr forums; always some dumbass kid talking about his dad's car.

Anyway, my son and I rebuilt the motor on his 94 325. (without the cam locking tool!) Runs great, but the driveability was goofy; the dealer checked and after I "confessed" to rebulding the motor, finally suggested (aside from replacing the entire ECM) that I should have replaced the torqconverter. "they do wear out". Didn't know that, and haven't done so yet.

 

This thing is still hiccuping at partial throttle. Pinging a little as well, but not nearly as bad as it was before I changed out that cap and rotor. I still think this issue is an 02 sensor starting to die out. Would not surprise me though at 245K miles, which is pretty impressive if you ask me. It does smokes for quite awhile till it warms up too. Could be head gasket, could be slight rich who knows. I've seen that sometimes has something to do with the PCV system on these things, but for the life of me I cannot find the dang pcv on this thing. haha. Of course I haven't looked entirely too hard on this thing yet.

 

did you check yer mas air flow sensor? those things fail in that car and will not trigger codes.

 

I would like to second jaylstro's post, the MAF can get dirty and that really screws things up... as long as it's not a karman vortex type MAF you can pick up a can of mass air flow sensor cleaner for 5 bucks and it may help you out some with the pinging... and have you tried to just replace the tps? those things are just a potentiometer and the resistive material will wear out a dead spot in the places where the throttle sits at frequently used speeds (like if you consistantly go to 70 and set the cruise)

 

MAF has been leaned, door moves freely as well. Have not rested it though. IACV has been cleaned as well. the TPS is not a throttle position sensor on these, it's a throttle position switch. it either one of off. Has three positions basically idle, cruise and full throttle. TPS has adjusted several times and has been tested for continuity.

 

LMAO.
Marriage is like a deck of cards.
In the beginning, all you need is two hearts and a diamond.
By the end, you wish you had a F'ing club and a spade.

All seriousness aside, on 325i, it was overhauled, then about 1 yr later started running rough, stalling, total BS. Totally stumped. So drug it down to the dealer, his code said it needs injector seals. WTF? We replaced those, I know.
But labor and shipping aside, they're 10cents. So we did. One hour later (after having AAA tow it home), and saving the $350 they wanted for labor!!
/insert-egg-on-face
Damn thing runs great now.
/end-egg-on-face

 

you know what, I've been chasing and entertaining the thought of a vacuum leak, but the inj seals didn't even cross my mind. Certainly would cause a vac leak though. Maybe even an exhaust leak, but like the 22r's the rockers are loud so I probably wouldn't even hear it.

 

does it have barometric pressure or MAP sensor? i know not all mass airflow systems use either of these but some do for redundancy... maybe bad sensor? that is if the vacuum leak deal doesn pan out for ya... if you have access to a smoke machine, those are awesome at finding intake and exhaust leaks

 

No MAP just the MAF/TPS.

 

We just ordered some a set of these from EBAY. $80 shipped

http://cgi.ebay.com/ebaymotors/NGK-E...Q5fAccessories

 

Blue???

They must be good then!

 

heh, consider these things sell for $170-200 normally, They better be.

http://www.amazon.com/NGK-54260-EUC0.../dp/B001RM6HM0

but then again even the bosch plug wire sets for this car are $193 at Autozone.

And the duralasts are $99 but do not come with the wire shroud like most others.

 

For My Reference

The engine of e34 535 uses AFM unit to provide information to the computer about the amount of air that enters. The unit uses a flap reinforced by a spring that continually presses the flap against the air flow. The spring is subject to relatively high temperatures which make possible for it to lose its resilience and gain more lax with time. The result is misadjusted AFM sensor that provides output inconsistent with amount of air that flows into the engine. Oxygen sensor as well is a subject to a change as it ages. Here I provide information on coadjustment of the AFM and oxygen sensor to insure correct operation of the system.

Introduction...

The flap of the AFM is attached to a horn that swings an electrical connector along resistive track providing variable resistance depending on position of the flap and therefore on the amount of air passing through. The variable resistance provides variable current at given voltage, informing the computer of the amount of air entering the engine so that it can adjust the air/fuel mixture...



Some theory...

The spring of the AFM unit is in place to insure that the flap does not wander but is continually pressed against the air flow to provide instantaneous response to the change in the amount of air passing through. In fluid mechanics the scenario is expressed by a relation involving momentum of traveling fluid and the impulse it imparts onto the obstruction:

mV=Ft

m - mass, V - velocity, F - force, t- time.

The velocity of traveling stream is differenet before the obstruction from after the obstruction since the stream experiences compression due to the change in the amount of space provided for passage. This results in formula:

m(V1-V2)=Ft

where V1 and V2 are stream velocities before and after the obstruction. This formula translates algebraically into the relation:

F=(m/t)(V1-V2)

Where m/t is mass of material passing through in unit of time expressed for example in units of "kilogram per second". The flap of AFM unit experiences the force F as the stream passes through which counteracts the effort of the spring to place the flap into position for the amount of air passing through. The formula tells that this force is affected by the mass of air passing in unit time as well as the speed of passage. Essentially "mass per unit time" means density, so density and speed of passing air affects the inclination of the flap.

The density of the fluid can be decreased by providing an opening next to the flap for some air to escape. In this case, the flap experiences less stream density and does not move as far. This type of adjustment is provided by a bypass screw within the AFM unit that channels some of the air before the flap outside, around and past the the flap, back into the intake.

Increasing the tension of the spring attached to the flap makes necessary greater density (and speed) of air to pass through in order to provide given inclination of the flap, therefore, the tension of the spring is also directly responsible for the balance of air/fuel mixture achieved inside the engine. If the spring is tightened - greater amount of air must pass through for given inclination of the flap resulting in leaner mixture. If the spring is loosened - smaller amount of air must pass through for given inclination of the flap resulting in richer mixture.

Since the spring is subjected to high temperature environment it is susceptible to gradual change in its tension, losing its ability to provide as much springiness as it did some time ago. This makes necessary an adjustment.

In order to adjust the spring tension some means of observation are necessary to tell how tight the spring should be. A voltmeter connected to oxygen sensor provides good means of observation as to the strength of the spring. The oxygen sensor is capable of provision of voltage in range 0-1 Volt that reflects the amount of oxygen that passes through its sensing tip. The computer reserves voltage band above .8V for "rich" condition and the band below .2V for "lean" condition. Within these bands the system is not capable of providing adjustment to the mixture which is done by variation of fuel injector pulse time and stores a fault code in the memory respective of the mixture condition. The functional band .2V-.8V privides a "space" of .6V for the system to operate, which is divided in two equal ones of .3V for adjustment within leaner and richer zone. The middle is obviously .5V, equally spaced from .2V and .8V.



The graph of oxygen sensor response shows average curve and its margins for voltage the sensor provides in relation to the mixture, with ideal mixture of 14.7:1 parts of air to fuel (Lambda = 1.00) providing most efficient combustion. The variation in output voltage within the space .5V +/- .3V results in variation in +/- 1% in mixture from ideal ratio.

This is the region of operation for a balanced system...

The principle...

The principle of adjustment is to set the system into the mode of operation in which the fuel injection data maps essentially control the engine within rough limits of most efficient mixture without interference of the oxygen sensor. The system provides injection maps as means of crude adjustment of the mixture to which oxygen sensor is simply a tool for "fine tuning". The stronger AFM flap shifts the course of operation to leaner mixture domain, the weaker flap obviously shifts the course of operation to richer domain. The objective is to set the course along the acceptable band of operation of the oxygen sensor .2V-.8V within which it can be used as a fine tuning tool without an over run out of margin of injection map.

Tools...

1 - 5 mm allen wrench
2 - Screw driver
3 - Multimeter
4 - Switch
5 - Wiring that satisfies the schematic shown further

Preparation...

The cover of AFM unit must be carefully pried off. The spring is clearly seen right below the horn that slides a contact along resistor track. The wheel holding the spring is secured by a clip which should not be touched. Instead, a crew driver must be placed against a pin protruding next to the wheel. To move, insert the tip of the scredriver between two cogs nearby the pin, and while reclining the screwdriver against the pin, gently rotate the wheel, in increment of one cog. Make sure that the wheel is marked prior to movement.



The direction of motion of the flap due to air flow is counter-clockwise from the point of view of the picture frame. the spring is clearly shown to resist that motion, being wound in opposite direction. Turnintg the cog wheel clockwise, tightens the spring, resulting in greater effort to move the flap open by the air flow. This necessitates greater air density, making the air/fuel mixture leaner at given position of the flap.

To tune the system, an allen wrench is used on the screw found in a hole on the underside, next to the outlet of the AFM unit. The screw is threaded across an air bypass channel for mixture regulation. As it is turned in, the passage area is made smaller increasing density of air stream before the AFM flap. The flap therefore turns farther in since less air is allowed to escape through bypass channel, making the mixture richer for given air mass flow at filter intake.



The wiring connects pins 3 and 4 of the oxygen sensor to the main wiring harness in order to provide power to the oxygen sensor. Without the power it cannot stay hot and does not provide voltage.



Procedure...

Disconnect the hose leading to evaporative purge valve from the charcoal canister at the point of connection to charcoal canister to avoid entry of gas fumes into the engine. The hose must be blocked to avoid entry or air as well. Reconnect after the procedure.

Warm up the engine and then stop it. Connect the jumper wires with the voltmeter and the switch as shown. The switch must be in disconnected state.

Turn the screw of the AFM in all the way till it stops. Count 3 turns as you turn now counter-clockwise. This is the base setting of the screw.

Restart the car. Observe the voltmeter display. There are three scenarios one of which can take place:

1 - Various readings that switch fast and haphazardly between about .8V and about .2V
2 - A relatively steady reading above .5V
3 - A relatively steady reading below .5V

Solutions:

1 - Turn the AFM screw one full revolution clockwise richening the mixture. You should see the reading turn steady above .5V. If the reading does not turn steady above .5V the mixture is too lean - turn the cogwheel of the AFM counter-clockwise, by one cog. Reset the screw to base setting - three full turns out from full stop, and repeat the test.

When the reading does set steady above .5V the "rich" margin is good.

Now turn the screw back to base setting, and then turn it once again - one revolution counter-clockwise. You should see the reading turn relatively steady below .5V. If the reading does not turn steady the mixture is too rich - turn the cogwheel of the AFM clockwise by one cog. Reset the screw to base setting - three full turns out from stop, and repeat the test.

When the AFM is adjusted for crude operation within the band of operation of the oxygen sensor, turning the screw clockwise one turn from base setting provides relatively steady reading above .5V, turning the screw counter-clokwise one turn from base setting provides relatively steady reading below .5V. When this condition is satisfied the AFM is adjusted - the screw must be set to base setting before adjustment with gas analyzer.

At base setting the voltage fluctuates haphazardly as a result of engine control by mapped data - the system is not able to keep the mixture at steady state with disconnected oxygen sensor due to the fact that any given stroke is not same as the next one in miscroscopic view. That's the reason why oxygen sensor is used.

2 - A relatively steady reading above .5V signifies rich condition as mentioned just above. Turn the cogwheel of the AFM clockwise by one cog, to allow more air at given position to make the mixture leaner. Reset the screw to base setting - three turns out from full stop and repeat the test.

3 - A relatively steady reading below .5V signifies lean condition as mentioned just above. Turn the cogwheel of the AFM counter-clockwise by one cog, to allow less air at given position to make the mixture richer. Reset the screw to base setting - three turns out from full stop and repeat the test.

 

more reference

Erratic idle performance of the engine is often attributed to quality of ignition components, Idle Control Valve, AFM sensor, Throttle Position Sensor, etc. A part of fuel injection system that is often ignored is Evaporative Purge System, cosisting of a canister that retains gas fumes within the tank, and a valve that directs the fumes into the engine. The valve is subject to blockage by charcoal from the canister, which results in fixation of the valve in open position responsible for introduction of unmeasured air into the engine. The performance of the engine at idle suffers greatly, and fuel economy and drivability problems may ensue. Here I share my experience of opening the valve and cleaning it to restore idle performance.


Introduction...

Evaporative purge system performs two important operations in E34 application. Primary purpose of the system is entrapment of fuel vapor produced in the gas tank in order to ensure cleaner environment. Secondary purpose of the system is provision of ventilation for the gas tank by allowing outside air to enter the tank and take the space left behind by used fuel.


Theory.

The block schematic below shows the currents of outside air and fuel vapors in evaporative control system.



The charcoal canister provides a way for outside air to enter into the system to take place within the volume left behind by the used gasoline. The canister has a filter and openings at its bottom in order to make this action possible. If the blockage occurs along the line from the expansion tank to the charcoal canister, the travel of air may be precluded resulting in implosion of the fuel tank.

Besides having the filter for the outside air, the canister is filled with charcoal that traps the fuel vapors to be used by suction of intake manifold when the engine is started.

The evaporative purge valve makes possible for the vapors to enter the manifold. Its normal state is open, it is switched closed by application of voltage by the engine management computer.

Along with the vapors, air that enters to take place of gone gasoline in the fuel tank is also allowed to enter the intake manifold.

Faulty evaporative purge valve does not provide closing action at application of voltage on its electrical input. This results in constant introduction of unmeasured air into the intake manifold through the charcoal canister and rough idle operation is very likely to occur.


Evaporative Purge Valve.

The valve has very simple construction. Its body consists of two parts connected at the rim of one part wrapping the other. Inside a flap that restricts motion of fluid is designed to be attracted magnetically by the induction due to application of voltage at the electrical input of the valve. As the flap is attracted to the coil, blockage of the path is established resulting in inability of fluid to pass through.



Travel of charcoal from the canister to to the evaporative purge valve is possible when the canister is old. The charcoal builds up between the outlet and the flap within the valve precluding the flap from motion to close the passage. Once the valve is not allowed to close, the unmeasured outside air is allowed into the engine through the bottom opening of charcoal canister, unless in extreme case, the charcoal build up between the flap and the outlet is so great that all passage is restricted. The passage of unmeasured air implicates rough idle condition. It may also be possible to hear relatively high pitched resonance from air passing through the canister.


To open the valve...

Tap with a small screwdriver along the seam of the rim between the inlet and outlet halves of the valve.

Alternatively, it may be possible to clean the valve by simply spraying brake cleaner into both nozzles.