tbi problems

[skylark]

Your tps is reading way too low. It should be .5 closed throttle to darn near 5 at wide open throttle.

 

[skylark]

I've seen this posted several times, why is advancing the base timing not recommended on TBI trucks?

Even a 2 degree bump is too much for stock programming. As soon as it picks up any knock it pulls timing. I used to bump my base timing too until I did some data logging on various trucks. The only time I recommend otherwise is when using a vortec long block with tbi for injection, then I use 4 degrees.

 

[Jrgunn5150]

My experience in this area is with Fox Body Mustangs

Even a 2 degree bump is too much for stock programming. As soon as it picks up any knock it pulls timing. I used to bump my base timing too until I did some data logging on various trucks. The only time I recommend otherwise is when using a vortec long block with tbi for injection, then I use 4 degrees.

Well that sucks lol, it also makes perfect sense, thanks!

 

[skylark]

You bet.

 

[mmeiers85]

Ok I might replace the tps, check timing and check fuel pressure and go from there. I'll post the results. Thanks fellas.

 

[skylark]

Ok I might replace the tps, check timing and check fuel pressure and go from there. I'll post the results. Thanks fellas.

Before you replace it, check for the 5 volt reference and 0 resistance on the ground side. I don't recall which wire is which but is extremely easy to figure out with a multimeter.

 

[mmeiers85]

Alright so I checked the timing, it was way advanced. Like past the tab, I would guess somewhere around 16* BTDC. So I brought it back to zero and it's much better, doesn't die anymore. It still idles up and down but it's pretty steady once it gets warm. I'm still gonna check some of the other stuff and see if I can make it better. Thanks guys!

 

[TylerZ281500]

most people do it anyways, stock cam heads intake and everything theres no reason for advance, my built motor i run at 0* still. when i datalogged my knock counts were lowest there, and i tuned it accordingly. advancing and retarding and anything timing has relevance to pre detonation and so on. depeindg on motor build and useage your timing may change slightly, but any stock motor you stick close to 0

 

[Jrgunn5150]

That's crazy to me lol. I've never seen a motor that didn't want some advance. Learn something new everyday.