94 thunderbird question

I have a 94 thunderbird, 180,000 miles on it. it surges back and forth at all speeds although, I did put it in second gear and brought it up past

3500 rpm and it seemed to run fine. I also noticed that my oil pressure keeps dropping to low then goes back to normal. I know that my valve seals are leaking cuz I get a puff of smoke when I start the car but, that shouldn't make the car run bad. I just changed the oil put new plugs, cap and rotor in. timing is good. I put a new fuel filter in and a pcv valve. I had a vacuum leak, fixed that. i checked the codes and I only get a code for the hego sensor but that has been like that for about 4 years now. the car always ran great. I would appreciate any help. thank you
Reply to
j
Loading thread data ...

Maybe IAC valve or TPS, maybe clogged cat. The oil pressure sounds like a clogged pickup if the change doesn't correspond to RPM. Put a mechanical gauge on the oil port to see what actual pressures are at various RPM (with engine warmed up).

Reply to
Sharon K. Cooke

Well, I supect that code for the EGO sensor might reflect that it's fouled up.

Your oil sender is a 'fooler' switch, if it's wavering that is not a good sign unless it's an electrical problem which it may be. And which might reflect on the 'surging' at any speed.

When i've had that it was related to a bad ground on the computer harness.

Or it could maybe be the block to firewall ground strap.

OR you might have been using a very famous oil and the engine, including pikups or returns, is all sludged up. too many possibilities, sadly.

Reply to
Backyard Mechanic

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.