I'm getting a lumpy engine at partial throttle during cruise in my 01 disco at about 2000 rpm. It's fairly smooth at idle and at 50% to full smooth as butter. I only have a code for rough road p1530 or something of that nature as read by my scan gauge. The only thing that looks out of the ordinary is that my tps reading on my scan gauge fluctuates and only stays in single digits on my scan gauge ( this is odd because the reading on the tps when I used to have it hooked up to my d1 would read 0-70 when the throttle was pressed all the way in) so I'm thinking it has something to do with it. This is a new engine for the truck and I haven't put all of about 35 miles on it. I checked plug wires and vacuum leaks.

I'm thinking it either is the tps which I'll pull the one off the other motor or something to do with the ecu needing to learn the new setup ie fresh motor with new to the truck sensors.

Any pointers would be greatly appreciated

Thanks in advance

-nate

 

http://enginecodemaster.com/landrove...rovercodes.php

Engine Code: p1590

Land Rover Engine Code: P1590 = ABS rough road signal circuit malfunction Hardware is OK, but SLABS ECU is sending an error signal. DTC P1590-P1592: ABS - ROUGH ROAD SIGNAL CIRCUIT MALFUNCTION Description When the vehicle travels across rough terrain, or on rough roads the ECM could falsely interpret suspension vibrations as a misfire and invoke engine misfire protocols and/or set a false DTC. The Self-Leveling and Anti-Lock Brake System (SLABS) ECU sends a rough road PWM signal to the ECM. Based on this rough road PWM signal, the ECM can suspend misfire detection for as long as the vehicle is travelling on a rough road. Rough road signal input is measured at ECM 40-pin connector C0637 terminal No. 34 (Red/Green wire on Discovery; Yellow/Pink wire on Range Rover). The SLABS ECU rough road PWM signal varies in accordance with changing road conditions. The rough road PWM signal operates at a frequency of 2.10-2.56 Hz. ECM rough road control is based on specific changes to the PWM signal. If there is a rough road PWM signal failure the Hill Descent Control/Anti-Lock Braking System (HDC/ABS) warning light may be illuminated. Diagnostic Aids The rough road PWM signal can fail in the following ways: Harness or connector damage. SLABS wheel speed sensor failure. If there is a rough road signal malfunction, the following DTCs may be set: If DTC P1590 is set, there is an ABS rough road signal circuit malfunction. Hardware is okay, but the SLABS ECU is sending an error signal. If DTC P1591 is set, there is a low ABS rough road signal circuit. Signal from SLABS ECU is shorted to ground. If DTC P1592 is set, there is a high ABS rough road signal circuit. Signal from SLABS ECU shorted circuit to battery voltage. Diagnosis & Repair When ignition is turned on and during vehicle operation, ECM checks rough road signal circuits. If expected signal is not seen, ECM will store a DTC. Using an oscilloscope or Snap-On(R) PAC ensure SLABS ECU PWM signal indications are consistent with road conditions. See ROUGH ROAD PWM SIGNAL INDICATIONS table. If PWM signal is not as specified, check circuits for opens or shorts. Check for poor power and ground connections and/or loose wires at ECM. See WIRING DIAGRAMS article. Ensure ABS wheel speed sensors are operating properly. Repair as necessary. When DTC P1590-P1592 repairs are completed, perform REPAIR CONFIRMATION DRIVE CYCLE "A" .

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How many miles on it, when was it last tuned along with 8 mm plug wires and what octane are you burning?

 

Mike fresh rebuild with new 8mm plug wires less than 100 miles

The ecu finally threw a code for 1 and 4 missfires so since they were on the same coil pack I replaced it with another one I had laying around fixed the issue so far put another 100 miles on it over the weekend smooth in all rpm ranges

Note to others planing on sealing engines be prepared for odds and ends to go wrong even though everything worked when you took it apart