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88PowerRam50
04-27-2011, 07:39 AM
88 Ram 50 2.6L mt, have tried everything but replace ECU to get consistent lower rpm, low torque performance. Rebuilt carb and distributor, new plugs, wires, TPS, O2 sensor, coil, checked for vacuum leaks, checked temp sensor. Still pings and bogs down sometimes usually in higher gears when asking engine for more power. I've got a "new" Cardone reman ECU. The Dodge shop manual doesn't spell out a replacement procedure. Is it simply unhook battery, replace ECU and re-hook battery? Does the "computer" need time/miles to relearn the engine inputs/feedback? Please advise and thanks. Randall

4doorciv
04-27-2011, 03:12 PM
This is a plug and play kind of thing. You are thinking about the obd2 system that is far advanced compaired to ours.

You've checked everything like recheck proper spark plug gap, check for vac leaks, clean egr, fuel filter, etc? Since you have the ecu I guess give it a shot. Chime in if it doesn't fix your bog problem.

l.k.
04-27-2011, 08:53 PM
keep us posted im sure between everyone here it will get taken care of...goodluck man

Ram50Man
05-03-2011, 11:07 AM
I had a similar Bog problem, but mine was during acceleration, an gong up hills, I advanced the timing on the distributor a bit, and viola problem solved!

LSR Mike
05-03-2011, 01:58 PM
Setting the Base Timing is a Special Procedure, you have to ground a ECU pin (Plug in the Engine Compartment) to put the ECU in adjustment mode, i.e. not controlling the advance/retard of the timing. Set the base Timing at 3-7 degrees BTDC. And changing the ECU is relatively easy, Fricking plugs can be a little sticky but think about how many years it's been in there. The truck will run just fine, It will re-learn, or learn in this case, long term fuel trims and the like which will improve your mileage over the initial install, nothing huge.

88PowerRam50
05-03-2011, 02:24 PM
Please help me understand which pin is to be grounded and how to ground. According to the Dodge service manual, the #10 pin goes to the ign.coil neg terminal (engine speed sensor), #2 pin is ground for sensor and #11 is ground. Also recommended timing is 7 deg BTDC plus or minus 2 deg. What do yo suggest, 7 or less? The harness plug for this ECU (in cab near glove box)

LSR Mike
05-04-2011, 07:04 AM
Ok, first, hook up your timing light, look at the timing marks, use some white out correction fluid to highlight the markings on the cover and on the balancer if they're hard to see. as you rev the engine you will see the marks move around.

Here's the Plug, thats the passenger side above the fender well.

http://mmeierle.com/Timing%20Plug.JPG

remove the cap, use a jumper wire with alligator clips or whatever to a nice metal ground in the engine compartment.

When you look at the timing marks again with the light, and rev the motor, the marks should be steady, indicating the ground is good and the ECU is in the set timing mode.

loosen the distributor clamp bolt (12mm IIRC) rotate the distributor till you achieve the desired value.
Haynes Manual says :

2.0 - 2.4L 4 cylinder engines 3-7 degrees BTDC
2.6L 4 cylinder engines 1989 and earlier 3-7 Degrees BTDC
1990 and later 6-10 degrees BTDC
3.0 V-6 engines 3-7 degrees BTDC
* refer to the Vehicle Emissions control information label in the engine compartment: use the information there if it differs from that listed here.

Tighten the Distributor clamp bolt.

Re-check the timing is still the correct value.

Remove the jumper, replace the dust cap, take a test drive.

88PowerRam50
05-04-2011, 12:32 PM
Hey LSR Mike, I didn't find the pigtail you show on my 88 Ram 50 2.6L mt. I took a picture of the same area on my engine, but don't know how to insert without a url. Suffice it to say I'm still in the dark on how to let the "new" reman ECU learn if possible on this year and model. Appreciate your insights, still not sure if they apply to me. The under the hood label and the original Dodge Service manual neither mention this "Special Procedure", though I know sometimes everything is not covered in the first issue. Thanks again. still having the same problem with loosing power SOMETIMES, when going up a grade or trying to accel, usually in the higher gears. Maybe I need to start a new thread and list all thats been tried so far. Any suggestions will be welcome. Randall

LSR Mike
05-04-2011, 02:29 PM
you have a carburetor, This is for a Fuel injected engine. Never mind.

Ram50Man
05-08-2011, 10:16 AM
Wow, good step by step though.