1999 x308, AJ27
The car will get up to the maximum 110km/hr highway speed, the legal speed here in Austalia easily, but when im going up a hill at say 50kkm/hr and I press for power engine does not rev up, even with pedal to floor temporarily.. but then it will rev up and change gear.
Its like a missing response, yet still lacks the v8 power you expect.. ie no kick.
I have noticed this on up hill acclerations... not on straight roads, yet I havnt noticed a kick in acceleration even on straight roads.


Im thinking it could be 3 things.
Firstly I must state that the engine was blowing oil in the air filter due to a cracked breath pipe previously which is now all fixed.
This excess oil may have clogged catalytic converter im thinking OR dirtied the o2 sensors.
MAF sensor was cleaned., New plugs, new air and fuel filter.
I also believe the injectors are a bit noisy on acceleration, quiet on idle though. Could it be clogged fuel injectors?.. the fuel filter didn't seem too bad when I changed it.
Car is not throwing any codes.


So what will cause the missing "kick" in acceleration- Im thinking cat converter, o2 sensor, clogged fuel injector. I understand that to check for a cat converter one needs to drill holes before and after the cat.. is there access for this. Would hate to do that if its something else, so whats the most efficient route to check here?


How to test for these, which is the easiest first check.
best regards
Peter

 

I just thought about this and concluded that it cant be the Catalytic converter as the engine DOES NOT REV when I press the pedal for power initially (up hill)... pedal will go to floor and no response, then after pedal comes back some power will kick in 2-3 seconds later.
If cat was blocked, exhaust would not be able to exit system, but engine should still initially rev up to my mind.


Sounds like a fuel injector (noisy on acceleration) , MAF (cleaned with electronic cleaner), o2 sensor which mixes fuel/air ratio(maybe dirty from oil problem previously).
Advice appreciated.


Peter

 

Check your fuel pressure. There is a schrader valve on the fuel injector rail.

 

I assume that you have an OBD reader, as you said it wasn't throwing any codes. Have a look at the STFT, (short term fuel trims), if they are hovering around 0 on steady throttle, then your O2 sensors and cats should be ok.

 

Also check the throttle cable and kickdown switch adjustment. Many times the cable has either stretched or slipped in adjustment and you only get 70% throttle.

 

God yours sounds a LOT like what mine is doing. I haven't taped a fuel gauge to my windshield yet and driven it to confirm a fuel pressure issue, but my transmission will not kick down properly...when I push the pedal to the floor it hesitates for 2 seconds, then kicks down to 4th gear, waits a second or two, then kicks down again to 3rd gear and starts to pull. It also has power sometimes, other times feels to be down on power.

I'm thinking the transmission fluid level in mine may be low because I changed the radiator and never topped the fluid up and since it has an internal trans cooler, I inevitably lost some fluid inside the radiator itself....

Curious to see what you find with yours though. I put new plugs in, clean air filter, new fuel filter, new plenum gaskets, cleaned the intake manifold and throttle body thoroughly while they were both apart as well as cleaned the ports on the heads lightly by hand...

I'm going to check the throttle cable adjustment etc tomorrow as well on mine, but keep us advised if you find anything! I'm debating whether I should try some of the Multi-Vehicle ATF that I've heard will work since it's just a top-up I need and I can't confirm what fluid is actually in it, but the Technician in me tells me to just order some ESSO and a Trans Filter kit online and service it all at once....

 

How does it behave in Sport mode? Also, the kickdown switch can be faulty you can check it with a meter pretty easily.

 

Im not familiar with this kick down switch, will have to do work on it.
I have not driven the car in sport mode ever, soon will after I finish the brake job im doing, new pads, disc, brake oil.


In essence when going up a hill and I press for power on pedal, if pedal is at 50% of its travel initially as an example , then when pressing for more power, there is no reaction even if I push to 100% pedal depression. then I release pedal, 1-2 seconds later power will come to a degree.


Can someone briefly explain the kick down switch, location ,operation... I will be sure to look it up time permitting.


best regards
Peter