1993 camry 4 cyl. engine with 260K great miles!

It was running great with about 21-22 MPG, but I've run into a problem lately...

I don't have any power or acceleration at all when I step on the gas pedal. The car just moves along with no "punch" at all if I need to get on the freeway or get out of someone's way. When I do punch the pedal, it hesitates and stutters (a little bit) until it gets into higher RPM's. It feels like it's flooding with gas or something. My gas mileage has sunk to a terrible 10-12 MPG right now too. It idles tight @ 900 RPM and doesn't stall or miss, but seems like the engine is running a little rough (if this makes sense at all)

maintenance done the last few months-
- sparkplugs, sparkplug wires, distributor cap & rotor, air & fuel filter, oxygen sensor.
- checked the timing and it is dead on.
- cleaned the EGR valve with carb cleaner. (didn't have alot of gunk build-up)
- sprayed the IAC valve inlet with carb cleaner, seems OK

I guess it's either the ECM or something else?????

any thoughts???

 

A few things to check: low fuel pressure, ign coil, coolant temp sensor for ECM, perhaps a vacuum line leak.

Seldom does the ECU go bad, this would NOT be the first place to check.

 

thanks toyomo...

I replaced the coolant sensor and that made a huge difference! amazing what a $18 part can do for how the car runs.

I still have the exact same stuttering and hesitation, but with alot more acceleration and great MPG from what I can tell so far after changing the CTS yesterday. Changing the CTS made a huge difference!!

At times I can really feel the engine accelerate and run smooth when in higher RPM's around 4K and up...

the problem is more noticeable with the A/C on, assuming the drag on the engine from the compressor makes the problem more predominant.

You still think I should look at the Ign coil and fuel pressure next???