bdr_one

I have a 93 Accord that feels like the converter is locking and unlocking. I have replaced that TCU. Cleaned and replaced the solenoids changed the fluid.still have the same problem. The question is there a dirty sensor,a bad sensor,wheel sensor or something I missed that is making it lock and unlock Please help

MAD_MIKE

Upper pair of solenoids are what control the lockup function in the transmission.

Verify battery is fully charged with clean tight connections.
Verify engine, transmisison, and harness grounds are clean and tight.
Verify shift solenoid wiring/connectors are not damaged.
Verify the solenoids filter is not clogged.
Verify the solenoids make a solid click when powered up directly by battery voltage.
Verify the TPS is not faulty or has a dead spot in the sweep*
Verify the wiring/connector to the TPS is not damaged.
Verify the Thermo sensor(to the ECU) is within spec.
Verify the MAP sensor is not failing.
TCC fully locks @ 50MPH, but will unllock due to changes in load, acceleration, and engine braking/down hill driving. Deceleration will cause the TCC to lock/unlock, part of the logic.

Verify everything when the engine is heat soaked.

Much of the transmission and TCUs operations are greatly affected by the condition of the engine and its sensors. Faulty engine/engine sensor may allow the engine to run 'normal' but will affect how the TCU commands the transmission to behave.

If it is the TCC locking/unlocking, you will see an RPM change in the tach.
If the Tach is not registering a change in RPMs, then it is not the TCC.
I would suspect and issue with EGR, causing a lean misfire and dead spot while at cruise RPM.
If the speedo is jumping there may be a wiring issue or the VSS is dirty or failing.
Pull the NM/NC sensors and verify they are clean. Off the top of my head I can't recall if these will affect TCC function, they will affect shift quality.
Verify any difference in pulsing if you are in D3 or D4.
Recheck for any stored codes, you will need the CEL and D4 lamp functional for this.

Verify it is not your own doing by pulsing the throttle. Lots of folks who learned to drive MT tend to pulse the pedal in an AT.

*Early ECU/TCUs are not very good at indicating a bad TPS, back probe the TPS when it is heat soaked and verify a linear voltage output change.

bdr_one

Trying to figure out what you mean by heat soaked.When starts that jumping the tach gauge does move stays at the same place.The only pulsing I feel is in D4.The TPS is brand new and adjusted to specs with ohm meter

jollyhonda

Does it only do this under a light/moderate load, such as going over a small hill and such? Check all your plug wires. What you may be experiencing is a misfire under light load. With the torque converter locked you will feel it and it will feel like a transmission issue. You may need nothing more than a tune-up.

Rob

bdr_one

Rob.I have done a tune up from rotor to the plugs, o2 sensors,fuel filter and pump

MAD_MIKE

When you have driven your car for a while and everything is fully heated up. Not just when you hop in the car for a 3 min drive to the store.
Not clear.
Does the tach change rpm when the pulsing occurs?
Yes, or no?

bdr_one

I have watched the tach and never seen it move.This is driving 40 miles to work and back home

MAD_MIKE

If the tach is functional, but you feel pulsing at cruise, check your EGR ports.
Most likely it is a lean misfire due to clogged EGR ports.

bdr_one

Mike, I drove the car and did notice that the tach did jump a little after a 15 min drive but not jump alot

bdr_one

I have done come to the edge with my car and thinking about putting it up for sale.I done everything to it to get rid of the misfire feeling.I have done remove the intake cleaned out all the egr ports,cleaned injectors,replaced fuel pump,o2 sensor,plugs,wires,rotor,dizzy cap,all new gaskets,seals,fuel filter,timing belt ,water pump,fuel pump relay, ecu,tcu,vss,cleaned iac,fitv,shift solenoids,rear engine mount,and a lot of other parts,I have lower ball joints and cv axle to still replace,also a ignition module.I have done the trans flush with Honda atf with the same misfire feeling.Don't know what else to do but put it up for sale

MAD_MIKE

Did you pull out each EGR port plug and clean them or only the EGR valve?

bdr_one

I pulled out every port plug there was and cleaned everything replaced egr valve to

MAD_MIKE

I know you stated you've replaced the FP and filter, but what is the PSI at the rail?
Have you done a compression check? What were the numbers?

bdr_one

With the old pump it was like 39 and 43 but the car starts better with the new pump the sock on it was clogged

bdr_one

I also replaced the tps and set it to specs,thermostat,engine temp coolant sensor.I drove home tonight and watched the tach again very close I didnt see that thing jump at all

jclapp

Hi, I am having the same issue with my 92 Accord. I had just replaced the dist cap and rotor, plugs and wires. Also replaced the coil. Then this started with the converter lockup. At first it felt like a misfire, but when it would occur the rpm would jump about 300 and did not happen when not in lockup speed condition. I have hear that there is a idle re-learn process so that the system knows your not just idling when cruising at null acceleration. Not sure if that is for the OBD1 system though.