i got an 87 TII and the problem is when you start to acclerate it starts to go lean,pop and crackles when its warmed up and also loses throttle resopne but before it is warmed up to operating temp its running great. if i get out let it cool down then start it later it'll run great until it warms up again. Has about 39lb of fuel pressure on idle after it warms up i havent had a change to chack it when its running bad.
brand new fuel pump wanted to know could it be a sensor causeing it to go lean.

 

what makes you think it goes lean?

 

i have a lean rich gauge

 

You mean hooked up tot he stock O2 sensor? That gauge might as well be there for looks only...the stock O2 is way to inaccurate to even bother looking at. Get a wideband and find out if you really are running lean.

-Joe

 

DP

 

Unusual symptoms..

I’d check the High & low voltages at the fuel pump next.

Also check the exhaust ground strap.
The O2 sensor relys on it.