Hey guys, lately my EF has been impossible to launch (as in take off from a red light) smoothly, it always bucks and jerks like I'm way off with the throttle application, but when cruising it's fine. It also kinda stumbles when i grab second, makes me look like a real noob 5 speed driver... Anyways when I was driving to work this morning I stayed in 1st gear for a long time as traffic was bad at probably 4000RPM for 30 seconds, then the CEL came on and it was code 1 - O2 sensor...

What's causing this? I changed the TPS earlier because it was throwing the code and drove like ****, now it's way better but still not perfect. TPS voltage is 0.45 volts closed. Fuel filter perhaps?

Any suggestions would be great, thanks in advance.

 

u might wanna check that TPS again.. to save u some headaches replace the throttle body with the tps on it already, as soon u start messing with TPS its kind of hard to get it perfect unless you tune it.

 

.45 is fine. stick the meter back on it and make sure it has a smooth gradual sweep up.

O2 nothing major, probably just worn out and is intermittently dying with the long term extra heat.

 

Running rich can cause a code 1

 

Yeah I'll double check the TPS, I also changed the O2 with a used one off my buddies wrecked EF and it only codes if I'm prolonged high rpm. Fuel economy is good too. Does any of the fuel injection components wear out?

 

Codes usually don't lie. But just in case make sure your IAT and your EVAC is working properly or that you didn't mix up the two plugs. My IAT and EVAC were switched and it through no codes it made car jump and buck like the motor mounts were broke haha

Just an idea

 

Ok well I'll go to pick n pull today and get a throttle body with the TPS on it and try that out, see if it at least helps the hard take offs etc.

 

Another thing I should note is that I couldn't get 5 volts from the TPS at WOT, only about 4.3. Is this normal?

 

Also if you have a lot of build up in your throttlebody it'll make it sticky and hard to get just the right throttle feel right and make it hard to launch perfect. Happened to me I just cleaned it out with carb cleaner and it wasa a little bit smoother. Just an idea.

 

Mine was acting like that before swaped tp sensor still acted up,
then swaped the map sensor and o2 was all better.

 

check ur timing too

 

Ok that's good info. You were getting an O2 sensor code but the MAP sensor fixed it? I'll change mine out today. Also, can I advance the timing a bit to get some more power or best to leve it alone?

 

if ur **** isnt running good now why u gonna make it run worse

if u advance ur timing belt will snap

 

LOL when have you seen a timing belt snap due to advanced timing? And I won't be advancing anything till I get the main issue sorted out. Thanks for the warning though, bro.

 

my boy did it twice on his z6

 

I'd attribute that more to inccorectly tensioned belt than advanced igntion timing homeboy. I can't see how advancing spark puts any additional stress on the timing belt.

 

two different motors

had the same idea advanced =more hp.for some idea

 

A couple degrees is mint. Improved low end and fuel economy. Ya don't go advancing it 10 degrees but a minor adjustment=more power to a small extent.

 

too much = fuct lol

 

You're joking right?