pippen

Ive got an 89 ea spak MPFI and it has a bad shudder ever now an then while idle. I noticed the oil pressure gets really low sometimes almost in the red. I was wondering would the shuddering bring the oil pressure down or could an oil leak cause it cos I think the rear main seal is stuffed.

TIKFD6

WHen you say shudder, does it nearly stall?
If thats the case its just the shudder dropping the presure as the engine is about to stall.
Adjust your idle speed.

pippen

The idle speed is fine, you could say it shudders about every 10 secs and some days the oil pressure will be fine and other days it will be low, but on the lower days the car shudder more freqently.

pippen

yes when it dose shudder it sounds like its going to stall but then picks up revs again

pippen

Fuel econ has gone through the roof aswell

TIKFD6

Have you made any mods to the car lately?
like thermo's, cam etc?

pippen

no just renewed head

TIKFD6

Was the head the same specs as the old one?

pippen

when you say the same specs do u mean it was also off a 3.9 mpfi or can the actual head be different?