RB20DET Trouble......HELP!

[masamunex03]

Hey, I was wondering if someone could help me out. I seem to be have trouble with my Rb20. The car seems to run fine when first started but after about five minutes of driving/warming it seems to want to chug. Between 2-3k rom is where it seems to not like gas. It feels like your rolling in 1st gear and sort of give it a little gas and then let go(jerky/jumpy). Not a very good explaination but thats just about what it seems to be doing. I've checked the ECU for codes and I'm getting a 55(all ok). The car is timed to 15 degrees. I don't know if it has anything to do with it but around 3k my Greddy A/F gauge is reading at the highest rich point. Help! please..... sobb.... hah....muffled fart...

[masamunex03]

BTW prior to this problem it was a perfectly running swap for a few months.

[Wulfgang]

Your Greddy A/F gauge becomes worthless for reading A/F the moment you step on the throttle. It will read at the highest rich point all the way from around 14:1 down to flooded when you stomp it Also, it should have read at the highest rich point before this problem.

But anyway. Could be a boost leak. Check your intake piping first.

[NISMObuttnutz]

Check the CAS, take it out and spin the knob, if it is very esy to spin and sort of notchy then it's toast. I've gone through 2 of those this week, MAKE SURE IT GOES IN STRAIGHT, my timing cover was tweaked so it wouldn't allow it to go in straight, and from my POV it looked straight, so don't make my mistake.

[vududoc]

AFM.....CTS

[masamunex03]

Thanks for the input everyone. I'm sure timing is contributing to this problem I'm having so I'm in the process of re-timing the engine because sometimes it likes to hunt. All my connections are secure so I'm hoping I don't have an air leak somewhere. At idle I'm around 15 1/2 in vacuum. If I recall, when in gear and slowly accelerating the vacuum is around 20-21(before spool). What is everyone's vacuum at around 1k(high idle) rpm. Would a front mount or unrecirulated bov cause a decrease in vacuum pressure? Cheers