Problems speeds first of all my car year is1993.when the tachometer get's 4000r/m then confuses and i loose the throtle.if i pull the throtle in netural gear until it gets 4000r and i let the throtle completely the car is fading.i have change the map and the multiplier and is ok the fuell presure and the avans also.please help...

Check for voltage then you may have to pull the dash

Hi Eveerei, If you're asking about the tachometer and not the speedo meter, that meter records the engine RPM speed and not the vehicle ground speed The tachometer at idle (when you stop at a traffic light, stop street or any other stop) should record an engine speed of about seven hundred to seven fifty revolutions per minute, at idle. It will increase in relationship to how hard you push your foot on the accelerator pedal. Hope this info helps you. Happy new year and regards John

The hesitates and misses is probably a chock problem, especially since when it warms up, it does great.

Since you weren't very specific on your indications, I thought a general troubleshooting guide might be helpful to you. But you might want to look on ebay for a shop maintenance manual for your vehicle if you plan on keeping it for awhile and doing your own maintenance.

This answer is applicable for many BMWs in addition to the one listed below.

Q

The tach and speedo work most of the time, but sometimes work sporadically.

A
Here is a write-up on the initial steps in tracking down a speedometer and/or tachometer problem.
Applies to: E23, E24, E28, E30, E32, E34 with speed sensor units mounted in the differential housing cover.

1) Speedometer - The speed sensor may be faulty. The sensor is mounted in the differential cover. Remove the harness plug and remove the sensor. Clean the sensor and measure the resistance (should be 0.0 Ohms). If there is any resistance higher than 0.0 (zero Ohms), replace the sensor. If the resistance reads correct, reinstall the sensor.

2) The wiring at the connector plug for the speed sensor (in the differential housing) may be faulty and corroded .... pull the boot back from the plug housing and inspect the wires and the pins.

3) The actual speedometer and/or tachometer head may be faulty. It may have a loose connection within it or a cracked circuit board.

4) The speedometer or tachometer head may be loose on the main instrument circuit board (do the gauges change or move if you smack the top of the dash, above the gauges?). Remove the instrument cluster and check the mounting of the speedometer/tachometer to the circuit board. See the attached issues of our Fast Times newsletter for assistance in removing the instrument cluster, on E30 3-series models (see the articles on replacing the PC board and replacing the odometer gears for info on the removal of the instrument cluster).

Fall 2005 Fast Times Winter 2004/2005 Fast Times
DIY E30 PC Boards DIY Odometer Repair


5) The plug that carries the impulse signal into the instrument cluster may have loose contacts. The plug for the speedometer signal is located on the driver's side of the back of the instrument cluster (on the E30 chassis). If you remove the lower dash trim panel (the one above the driver's knees), you can reach up and touch the plug. It is in a vertical position and has up to 26 wires in it. If you wiggle the plug, while driving, and the speedo comes & goes, you have loose contacts in the plug connection.

6) You may have a problem with the service interval PC board and it's NiCad batteries. If your oil change and service interval lights can not be reset (or will not stay reset for an appropriate time period), the PC board is likely faulty. This can affect the various gauges, including the speedometer and tachometer. If the PC board is faulty, I would suggest replacing it (after checking the other areas noted above). See the attached Fast Times newsletter article on replacing the service interval PC board.

In your specific case, I would suspect that you need to replace the service interval PC-board, if your service reminder lights can not be reset or do not stay reset.

P0320-is Ignition/Distributor engine speed input circuit. Inspect the wire harness and electrical plug ins in the area of the distributor. Replace the Ignition/Distributor engine speed sensor. This should clear up your Tachometer problem. Good Luck and happy new Year. From Ernie @ RedDeer, Alberta, Canada.

The speedometer cable could be broken or loose. The speed sensor is prbly your problem. Do you have a tachometer? If so does it still work?

it could be plugs and or high tention leads, causing missfire best way to check these is better at night open the hood of the car, run engine and see if you are getting a loose spark, that will be your high tention leads it could also be that when they get hot, they expand and start reducing the power of the spark to the plugs if you find that these will need replacing, to test spark plugs, get a pair of pliers and preff a pair of rubber gloves, pull the leads off each plug one at a time, if there is no change on one you pull of, that plug needs replacing, continue till you have checked all of them, hope this helps

Souds like the speedo cable / speed sensor has come loose at the back of the gauge cluster. Common problem easily fixed. Make sure it clips in fully next time.

Sounds like an internal cluster issue.

if its not a fuse check the speed sensor for the tach, and the oil pressure switch on the side of the engine block see if the lead came loose

I had the same problem with my 1995 Honda Accord V6 2.7L a year ago. It was a pain to have Honda diagnose the problem because it was intermittent and every time I took my car in to the dealership they said they couldn't reproduce the problem, but the longer you wait the more frequently your tachometer will fluctuate. I finally stopped by the dealership when the tachometer was jumping and they were able to diagnose the problem. In my case there was a faulty resistor in the ignition coil, but the entire ignition coil needs to be replaced. I don't know anything about cars but I know this fixed my problem. I went directly though Honda's service center so I know they charged me more than an independent repair shop but I'm looking at my invoice now and I paid $150 for the ignition coil and $200 for labor. After Honda diagnosed the problem I searched for "1995 honda accord ignition coil tachometer" and found that other people had the same problem and replacing the ignition coil was the fix. Hope this helps.