HELP!!! 2003 losing power up hills
sn2bavet
08-01-2012, 01:23 PM
Ok for starters I have a 2003 Buick century 3.1L Last week it started losing power when I was going up hills and when I pushed on the gas more it would just slow down even more and creep up the hill. So first thing we did was change the fuel filter, no change. Then we got out our trusty Haynes repair manual and it said to go get a code read-out we did and got error code P0403 -EGR system fault. So we replaced the EGR valve, still no change. Then we had a mechanic friend come over and he checked all the voltages going to everything and they were all good. So Haynes book said that if all good then the problem is with the PCM! We are out of work and short on money and this is why we are trying to fix this ourselves. So, we went to a LKQ used parts store and got a used PCM then went to the dealer and put it in ourselves and had the dealer reprogram it (the dealer mechanics were rude and very unhelpful and we left there feeling raped) Anyway,the car drove home doing the same thing but now it was misfiring when pushing on the gas as well. When we got home we hooked it up to the code reader and now it was giving a code for cylinder 1 misfiring. So, now we are stumped as to what to do. Is the used PCM bad? Did we waste our money on buying the EGR or the PCM should we get out money back and look somewhere else for the problem. The only thing we can think of now is to check the spark plugs but we are thinking that it will just be looking at the new misfiring problem and not address the no power up hills problem. Please help!!
HotZ28
08-01-2012, 06:57 PM
Unfortunately, you have wasted a lot of money using the Haynes manual & the dealer to try and resolve this problem. Apparently, you have secondary ignition misfire, which could be the coil(s), wires, or plugs. You should get some other opinions from reputable sources, such as an FSM, or independent ASE certified mechanics who have a good reputation in the area you live.
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