motoxrider295

I've been battling this issue for a couple months now, constantly my 99 TL (about 115k) has been lacking of throttle response, low end power I'm talking under the range of 2500-3000. Once it reaches VTEC you feel a nice instant power gain but its still as if its being dragged down by either lack of fuel or a sensor gone bad causing the wrong fuel mix because when I reset the ECU for the first 10-15 miles it runs like a TL should, quick throttle response, able to slightly break the tires loose with TCS off, and the power to get up to a good highway cruising speed without having to mash the gas. This issue happens about 80% of the time, no specific times of the day or motor temps does it drive nice. Only drives beautiful when: its cold or reset the ECU. Another symptom is after its sat for maybe an hour or two the first step on the gas I give it to go it hesitates for about a second and a half then goes but follows with no throttle response and lack of real power.

I've tried testing and replacing the MAP sensor, Intake Air Temp Sensor, TPS, throttle body cleaning, seafoam the intake and gas tank, and EGR cleaning.

I just have no other ideas to test before taking it to a dreaded repair shop or the stealer. Any input is helpful.

gold2003tl (90)

i dont know what to say if you already did testing and replacing the MAP sensor, Intake Air Temp Sensor, TPS, throttle body cleaning, seafoam the intake and gas tank, and EGR cleaning

maybe fsttyms1 can chime in

Gfaze

Is your CEL on? How long has it been since you've replaced your plugs? What kind are they? How about your air filter, is it clean?

motoxrider295

No CEL, does work though, plugs are probably under 25k miles old. I know they're Iridiums as to exact model not sure unless I yanked em back out. Air filter was replaced about 20k ago looks ok but that could be deceiving.

Gfaze

Well at the very least change the air filter. If it's restricted it can cause sluggish operation. I'd recommend a K&N filter instead of a conventional paper filter. The increased airflow should help with the throttle response assuming there isn't something else causing problems.

nhn23

iTrader: (4)

^ if you want to go his route, i have a K&N drop in filter thats about 2 weeks old, still brand new in box.

vannakam

check o2 sensors..... im chaning mine this weekend.. i have the same problem for past 9 months.... .. i have done eveything... to what ever you have replaced and cleaned.....

vannakam

my buddy had the same problem with his 2000 Prelude... Automatic and he didn't have a CEL.. same issue.. once he replaced his o2 sensors.. problem solved...

motoxrider295

Well sounds like I'm gonna give that a try, I also noticed my coolant boiling in my radiator, so I'm gonna do a flush today either the coolant is old or there's too much water in there I'm thinkin'.

vannakam

Update.: Changed o2 sensors and new battery...(interstate Megatron 2).. PROBLEM NOT SOLVED... and im like fuk this.. so i went home.. and thinked way back when this problem happened like 7 months ago... I went through all the invoices for the services been done .. and i came across a invoice saying replaced PCV Valve at a local Lube place.. i was a little suspecious wid this replacement for my car it was an aftermarket PCV Valve.... So the next minute i ran to the car straight to the dealership and got a OEM PCV Valve.. i noticed a little difference.. and i hear hissing sound from the PCV .. hose or the gromet.... im guessing it could be a vacum leak right?

ANC297

iTrader: (2)

I would guess that it is a vacuum leak as well.
Try fuel injector cleaner. It won't solve the entire problem, but it will help with the lack of throttle responsiveness.

vannakam

Well i put Redline Fuel Injector cleaner last nite.. and drove it .. buh it was a little better felt the power buh sluggish accleration.. *but guess wat*.. i can't beleive this.. it's actully the pcv gromet and hose.. dere iz a leak from pcv valve to the gromet... so what i did was took the pcv valve out and used a flat head and played around wid the gromet also wid the hose.. later installed.. took the car for a spin OMGGG.. accleration was so nice.... although it does leak a bit.. casue the pcv iz really loose in that gromet..

motoxrider295

Alright an update to my search for the cause, I've only recently flushed the coolant and changed the oil out for maintenance and now the power is back and equal through out the rpm's although one small issue still lingers. Once the motor has been sitting for maybe an hour, upon the restart it fires up no problem but once the gas is applied it studders no matter what percentage throttle you give it for maybe a second or two then takes off no problem. Still can't quite pin-point the issue. Doesn't do it at red lights or low rpm cruising, only when turned off then back on later.

gold2003tl (90)

i did stp fuel injector cleaner and that stuff works, i gained some good response and freed up some power. engine runs like new now.

check the tension of the throttle cables, both of them. make sure one is not tighter than the other or much much looser than the other. also check the spring return mechanism in the throttle and see if thats sticking or has extra resistance when giving it gas.