Hello,

I'm having issues with loss of power. Sometimes i'm driving my truck, it's performing great. Like it should. Other times it's not performing as it should. And i'm having to push the pedal to the metal. Don't really have a clue what could be causing it. I've got new sparkwires , plugs , rotor and cap , had new tps , iac , o2 sensors and all that stuff renewed trying to solve it, but no result.
The times it performs good , it's easily picking up speed, the times it's performing bad, i gotta hunt high rpm's to pick up some speed fast.

Now also when it's in 3rd gear in low rpm, 1500rpm by example something is bogging the engine down. It's having no power at all then, as soon i get above 2000rpm it has !

And also, when it goes uphill i'm having a dramatic powerloss sometimes..

My car runs on gasoline as gas also ( liquid petroleum gas ). It has this on both fuels.

I've been thinking i could have a clogged catalysator. But wouldn't this cause problems 24/7 ?

What other routes to check? Fuel presure etc won't be it as it does it on both fuel types...

Thanks in advance

 

Not sure what a "catalysator" is but a clogged or clogging catalytic converter will definitely act like you describe. They don't always plug completely immediately but can break apart causing loose pieces to plug and unplug.

Unplug the front O2 sensor from the cat and see how it runs. That is the test for the cat.

 

Thanks, first thing i will try tomorrow ! I was reffering to catalytic convertor, here in Belgium it's called catalysator

Thanks in advance

 

Also, it is normal my engine idles higher on a cold start?
Cold starts it's always around 900-1000rpm.
Else it's always 650rpm..

 

Yep, that's normal. The engine will run at higher RPM for a few minutes, until the coolant starts warming up. Once it reaches operating temp, Idle should be around 600 or so, in gear, with your foot on the brake.

As for the loss of power, yeah, that sounds like a failing cat. To test, REMOVE the front O2 sensor from the exhaust. That leaves a nice hole for exhaust to escape through, and yes, it's louder. If it runs better with the sensor out, replace the cat.

Have you checked your plenum yet? (intake manifold is two-piece, check the be-all, end-all plenum thread stickied at the top of this forum for more info on that.)

 

I did fix the plenum gasket about a year ago. Put in new bolts, grinded them a bit off so they fit proper & put a lil bit of locktite on. So that should still be good..

I did the test with the o2 unplugged. It might have droven a little bit better, but not as close as it is performing on it's good turns..

 

Did you just unplug the wire from the o2 sensor or did remove the sensor from the cat? The sensor needs to be removed from the cat.

 

Unplugged an removed aswell. Engine woulnd't start with it electrical connected.. so connected that again , and drove with the o2 sensor removed from exhaust..

 

Another check you can do is crawl under and hit up on the converter with your hand or rubber mallet and listen for stuff rattling inside of it. If it were mine and the cat was original with a lot of miles on it, I would change it out or get rid of it. They're kind of a problem waiting to happen (my experience anyway).

Something else that might help is to start running injector cleaner through your tank if you don't already. My truck acted up for a long time with the power/no power (most of the time no power) thing and cleaner fixed it.

 

I don't believe it's injector related, because i drive on 2 fuels. And have 2 sets of injectors on my car. With both fuel types , it acts up wierd..

Also, the car is in my possesion for over 120k miles. So yes, renewing my catalytic convertor might not be an bad idea!

Now i see i can order magnaflow cat's , but comments aren't that great so far i've read! Is there any brand / type catalytic convertor that breathes best?

Thanks,