I have my cars timing set where it needs to be but it feels like it is surging and i here detonation in the engine when i step on the gas pedal. When i move the distributor to where it runs good and doesnt pop, i get a code 33 map sensor. i have tried the iat trick but have not replaced the map sensor it self since i have heard it could also be an egr valve or a clogged cat. i am just frustraded, it ran fine until i had to remove the intake manifold to replace the damn colant bypass valve. in order to do that i had to remove the distributor and now it has gone to crap. any suggestions would be extreamly apreciated.

 

keep in mind my car is a tpi 305 with the l98 cam, i set my timing to 45* advance will the computer was still advancing and retarding, this gave me a quicker take off smoothed out idle and took away that sluggish feeling of 6* advance recomended by the factory. This will slightly kill your high end and will fail you on emissions due to nox levels. Make sure you use a decent octane i run Super 93 Exxon. So lessen that and play with it using im guessing good ole 87 octane. oh yeah my car was running like crap before hand