grampastoy

recently installed PI heads and intake from FRPP on my 97 4.6 Romeo engine. Now I get a lean burn side 1 and 2. have reset and check engine light reappears after 20-30 miles. car also has new 2.5 inch exhaust to flowmaster delta 50s. also K&N air filter element. cleaned MAF with tuner/cleaner. Bilstien shocks shouldn't matter. Car runs well. What do I change to eliminate check engine? 24lb injectors?

blackstallion666

first things first check for any vacuum leaks.

livefast1

check for vacuum leaks, check for exhaust leaks, did you get a tune for the pi heads? i would think installing better flowing heads would call for fuel trim adjustments as your providing the engine with more air, causing your lean condition.

grampastoy

Thanks for the help. Tell me more about the "tune" for the pi. Doubt this has been done. Thanks.

livefast1

with your upgrades all being installed at the same time your increasing the amount of air available to the cylinders, thus calling for more fuel. this could bring on a lean code as the 02 sensors will notice the increase in oxygen present in the exhaust. if everything checks out mechanically sound then you more than likely need a tune, a mail order tune using a programmer would do for your upgrades, a dyno tune would be better but will cost more.

grampastoy

Thanks for your input. Are their any specific programmers recommended? Or good used?
I did find a few hoses that were not entirely in place. One moved on 3/16 inch and the other 7/16. They are directly behind the paasenger cylinder head and down 5-6 inches. Made some large chopsticks to get a hold on them. Also reset the check engine. Will see how it goes.

ddmsgtr1

For our cars, SCT software is pretty widely used. You can get a mailorder tune from almost anybody who carries SCT nowadays, but most people have been recommending Brenspeed, but like livefast1 said, a dyno tune would be nice.