Contour Enthusiasts Group Archives Forums Modifications Duratec Performance Hiccough after K&N cone install (KINDA LONG)

hey everyone,
ive posted before but the problem seems to be getting progressivly worse. although its not too bad i do notice it and it drives me .

it seems to have started after i installed my k&n cone filter. i removed the little sensor that attaches to the stock air box and without anything filtering the intake i blipped the throttle and as the rpms were comming down it nearly stalled and hesitated back to normal.

so i put the cone filter on and left the little sensor "dangeling" and the car idles fine and seems good through the entire rpm range.

Lately i have noticed that under steady throttle anywhere in the rpm range or under normal to heavy accel. the car will "hiccough" as i mentioned eariler, it has been getting worse but it is by no means undrivable.

my first thought was fuel filter or after reading other posts maybe the pump or screen however, this problem occurs at empty, 1/4, 1/2, 3/4 and full.

i just today remembered what my car did with no filter (and no ididnt drive without one i just started it for a second) has anyone every had anything similar? i was thinking of just putting my stock setup back but i had to fabricate a diy connector from the tb to the cone filter and i used automotive adhesive to connect so its kinda permanint. i could remove it but it would be a pain and if it didnt solve anything then it wouldnt be worth it.

anyway, thanks for reading and any ideas or suggestions are more then welcome.

Thanks a lot evryone,
John

reset your computer, it should be fine.

how do i do that

Disconect negative cable on batt...then in the fuse block under the hood pull fuse # 4 and 11...wait 2-5 mminutes reinstall fuses and reconect batt....that should do it

OK, I think all of your problems have to do with the IAT sensor - Intake Air Temperature ("the little dangling sensor").

You see, what it does is measure the temperature of the air entering the engine and adjust spark timing and fuel based on it. The hotter the air, the less dense it is and thus less fuel is needed to get the right air/fuel ratio. Also, the hotter the air, the less spark the engine can handle before pre-ignition/detonation/"pinging"/knock.

OK, so the computer is always sensing the engine compartment temperature. When the air coming into the engine is hotter, you can get too much spark. The hiccup could be the knock sensor pulling timing out because the PCM is giving too much spark. You will also be running too rich, which by itself could give you a bit of stumble if the plugs are getting fouled.

When the air entering is colder than the sensor reports, you aren't getting enough spark (robbing power). You are also running leaner that you should with regards to fuel. Too lean, and you get knock. If so, the knock sensor will (or should) detect that and pull a bit of timing. You may feel that, and it could also be the hiccup you mention.

BAT sells an "IAT Relocation" kit for just this situation (non-SVT removes stock airbox and loses OEM placement of sensor). You can buy it, or just look at what they do and fab something yourself. You basically want to get that sensor back into the post-filter intake stream. The SVT has it in the accordian (we get an extra hole for it).

Also, in the future when modding, if you run across a sensor you should try to put it back in a place where it can be useful. They are all there for a reason and 99.9% of the time it interacts with how the engine is run.

i figured that, but both my know it all friend and the guy at the performance store said it inst needed. now im the kind of guy the thinks "if its there, its dam important".

i will cut a hole into the rubber boot of the k&n and putting it there. that along with resetting my computer hopefully will do it. ill let you all know.
thanks for all the help,
John