I have a 99 camry LE v4 2.2l at about 280,000 miles now. I've replaced the engine with a 2001 camry engine but it's the same v4 2.2l. Recently I've replaced the entire erg system as well as most of the vaccume hoses and the plugs, wires and coils. I have managed to solve all my check light codes but now when I sit at idle the tachometer bounces about 100-150 rpm even while accelerating. I've already cleaned my throttle body and idle air control, replaced the o2 sensor and I don't have a catalytic converter any more.

I'm honestly completely stumped at this point anything would help!

 

Is the engine RPM varying or is the tach meter varying?

 

Both. The tach is bouncing like in the video and you can hear the rpm following suit. It's most pronounced when at idle but you can still notice it while driving if you watch the needle closely.

 

Engine lope.

Did the replacement engine ever run OK?

Did you swap sensors, including O2/AF, from old to replacement engine?

What were the codes?

 

Yeah this is the first time it's done anything like this. Yes I've replaced the o2 sensor already and currently there are no codes. The old ones were multiple cylinder misfires and erg malfunction. However I've fixed both issues and so I don't have any more codes.

 

You state when accelerating the RPM/engine still lopes?

Check for differences between the 99 and 01 engines fuel pressure regulator systems.

Check PCV system + leaks in large engine intake hose after air filter. + issues of poor coolant circulation through IAC valve.

 

It does but it's not as pronounced however I can feel it while climbing hills at low speeds. Once I hit highway speeds it's not noticable at all.

yeah we were messing around with the intake since I swapped out the throttle body so I'll double check the line after the air filter. A friend of mine said to check the throttle position sensor and another forum talked about the ignitor and the speed sensor. Could any of those contribute to this issue?

 

Speed sensor is for speedometer, ABS (if installed) and engine computer speed input. When car is stopped, the sensor will not be generating a signal.

TPS issues tend to result in engine issues at certain speeds (throttle position).

The 01 engine may have a fuel pressure sensor linked to the computer. The 99 did not.

Igniter typically works 100% or totally fails.

Since you swapped engine, might check any ground wiring points, wiring connections, etc.

Some owners have linked the issue to the fuel pressure regulator (inside tank attached to pump).

 

Thanks for all that info! It really helps! The more I can learn the better! I'll have to check the wiring and what not but I've had this engine in for about 3 years now and I haven't had this issue before. Now granted it might have been covered up with under lying issues because I did replace the fuel filter while I was trying to suss out a stalling issue. It feels like something I've recently changed would most likely be the cause which leads me to believe that it could be the vacuum lines. Is there a way to check if any of the vacuum lines have holes in them or anything like that?

 

If the issue started after working on the car it's always best to retrace the work.

Finding leaks in vacuum lines can be a real challenge!

The pros can use a visible smoke generator (heated mineral oil blown through a tube). A low pressure leak draws in the smoke. Pro model smoke generators are very expensive. One make a low cost unit. It does require a low pressure air source to force the smoke out the tube.

Sometimes spraying ether (starting fluid) can result in an RPM change (rise).

If you have an ODBII scanner can check for a higher fuel trim. The vacuum causes a lower A/F ratio (lean), the computer compensates with a rich trim.

Which filter did you replace? There is a sock filter on the pump.