AlaskanLS

A piece of advice for those that are facing poor mpg even after replacing all related parts. I have had problems with my car's fuel economy from day one. I have replaced every thing that one can think of, but no benefit (ECU caps, spark plug wires OEM from dealer, sparks plugs, ignition rotors, timing belt, ECT sensor, coolant thermostat, 4 O2 sensor OEM, cold start injector switch, water pump, AFM and the list goes on). I read about the famous ECU caps thread and tried that as-well and it made my car's MPG worse. I had no leaking capacitors or any rough idling problems with my car and it was running smooth before and after recapping the ECU, which tricked me to believe to change unnecessary parts that were not the cause of the problem. Finally I got tired of the car and was about to get rid of it but before doing that I decided to replace the ECU and as soon I replaced the ECU, bam! the car's mpg improved right away. I was getting 10 MPG before recapping ECU and after recapping It went down to 6 MPG.
So a piece of advice for those that are facing this problem. ECU are dirt cheap on eBay. Before replacing other parts, I would suggest to try another used ECU and check if that will making any difference. Don't be fooled by replacing caps will fix your car's MPG. Capacitors may or may not fix your car's mpg. I believe there is separate chip for controlling your car's mpg but no one knows which one is that. Your best option before throwing parts at your car for fixing poor mpg, is to take your car to a mechanic to check the fuel trims, which can help find the culprit for poor mpg 90% of the time.

For those whose coolant reservoir is leaking from the top, here is cheap fix. I had used Toyota FIPG to fix the leaking reservoir. Please check the pictures for better explanation. Don't use the silicon on the threads, just use it around the neck area of the plastic sensor that tells the ECU if the radiator is low on coolant.

python

iTrader: (4)

im thinking whoever did the caps on the ecm didnt replace them with the correct ones...i did mine as a preventative thing because i was sick of hearing about it..my mpg never changed

Superfast1

What's your MPG now w/ another used ECU? You should be getting around 17, 18 for mixed driving.