1996 GXE 5 speed, 273000km
New plugs, KS, fuel filter, cleaned TB, no ecu codes (0505)... It feels like I am missing a good 20-30hp... Will probably drop by the Dyno to check things out this week, but I was wondering what to check for... The O2 sensors have never been changed, would that rob a lot of power ? Are there any Engine coolant temperature sensor or anything that I should be aware of that could rob so much power ?

Any help will be greatly appreciated !!

Thanks

 

Did you install NGK spark plugs?

 

I dont think o2's would rob power if they are functioning right....maybe injectors could be dirty or something like that....but with that old of an engine its not a real suprise to have power loss just as a result of normal wear.

 

yes, they are NGK platinum. Well, this loss of power doesnt seem to be that related to age... I mean, I kinda noticed tonight that I lost most of the power below 2800rpm or so, it seems to surge ahead when hitting that rpm ?? I did clean my throttle body today. Would I need to remove it and clean it thoroughly ? Could I have blocked some of the sensors overthere ? I heard one of them served a purpose to provide some torque at low rpm ?


Thx

 

Following on my last ''self-reply'' is it possible that a bad EGR valve cause this kind of problem ? I know it did on my saturn, is it the same for my max ?

Thnx

 

Here is what the Haynes repair manuel say's it could be.

1) Incorrect ignition timing
2) Excessive play in distributor shaft (1993 & 94 models only)
3) Worn rotor, distributor cap, spark plug wires or faulty coils
4) Faulty or incorrectly gapped spark plugs
5) Malfunction with fuel injection system
6) Clogged air filter
7) Brakes are binding
8) Incorrect amount of fluid in automatic tranny
9) Clutch slipping
10) Fuel filter clogged or impurities in the fuel system.
11) Emission control system not functioning properly.
12) Low or uneven cylinder compression pressure
13) Obstructed exhaust system

 

If the surge you get is after like 3000rpm's....you might just have your air conditioning on. It robs like 10-12 hp.
I don't know though.

 

You might just have excessive carbon build up. You might try throwing some seafoam through your cars intake and BG44k through the gas tank.

Others that have had your symptoms somtimes pointed to a coil pack. I would check the resistance on your coils just to make sure.

 

The coil packs have been replaced, I will look at Aicv and EGR this weekend... Maybe tps ?