THERE ARE NO BORING DAYS IN HUMMERLAND!

Well, in the past few weeks, my '05 seems quite "lazy and heavy" when accelerating. Accelerating from 0 is usually not a problem but, to accelerate say from 40 mph I have to press the gas pedal more than half way down before noticing a reaction (which is quite poor). No check engine light and no trouble codes Also no misfiring on any cylinder.

A month ago I got a low efficiency cat converter code but other than that nothing and my exhaust seems to have a few tiny leaks before and after the cats. But again no code..

It seems to me that when I use a fuel additive, it drives a little better or, maybe it is just psychological.

I had my injectors serviced (I don't know how well) months ago and a friend is advising me to replace them all at least with refurbished ones. I see different ones on eBay... some say 420cc 42 lbs, others upgraded 23 lbs or 4 holes upgraded, etc... As I can't afford new ones right now, any advice on what to get?

Thanks!

 

you really would have to monitor your short and long fuel trims your oxygen sensors and mass air flow and fuel pressures plus check your engine load percentages when the problem happens so most likely would need to data log and drive it hard to find your issue. could be as simple as a clogged air filter or can even be restricted or clogged exhaust those are only 2 examples of conditions there are more that can cause it to bog down as well like fuel starvation.

 

Thanks bronxteck!

So, since I don't get any misfires, you would discard injectors altogether?

I have never logged live data from the scanner but I will give it a try...

 

you can start with checking your air filter and cleaning the mass airflow sensor with a can of MAF cleaner of your choice.

 

Logging data is also not going to help if you are not pretty well versed in how to read and understand what the data is telling you....

Couple of good tips already. This is just one of those things that could have a hundred different causes though so you just have to start going a bit at a time. Have you ever done a tuneup? Maybe it is time for new spark plugs and plug wires (if you do, please, ONLY use ACDelco plugs). If you have a Tech2 (and some other shop grade tuners can do it as well) you can try a crank variation relearn as that can sometimes get a bit off over many years. Disconnect battery for about 20 minutes (or use a Tech2) can reset the long term fuel trims which will take a few days to sort back out might also help. Just trying to think of a couple of low cost things to try....

 

Exhaust leaks before the cat is a sure sign that it could be plugged.