Power issue - could use some guidance

Hey everyone- having some issues with my '03 tacoma 2.4L 4 CYL. Haven't been able to get it correctly diagnosed at several different shops, spent $$$ trying to figure it out. Leaning on the forum for some guidance

Issue: Check engine light on. Truck losing power, using oil. No oil leaks found. Runs extremely rough.

Completed trouble shooting repairs are: Spark plugs and coils- several different times. Replaced o2 sensors in front and behind catalytic converter. Replaced catalytic converter.

Each time we replace plugs and coils, engine light goes off and truck runs fine for about 50-100 miles, then CEL comes back on and same issue returns.

Hopefully I've given enough information, trying to keep it short. Thanks in advance!

 

It really helps to know what code your getting?

Some 2 trip codes might take 100 miles to trip the light.

Just how much oil?? a quart for 100 miles or more?

Mileage??

 

Thanks for the message, @Bivouac .

The code is 'cyl 1 misfire', which is the same one every time. The engine light does clear after we've completed the repairs and driven the required miles to get it to clear. Then it comes on shortly after I would say it burns at least 1 qt every 100 miles. Miles are 211,996 !

 

Need to check compression. Does it smoke? Oil has to be going somewhere. Either getting burned or leaking

 

What does that number one plug look like ?

Oil fouled or is it clean and fouled by a leaking injector.

I think a leak down test is in order then a compression test

good luck.

 

Ok, I'll get engine compression checked, thanks for the suggestion. Wish I knew more about mechanical issues with vehicles, thank you. I agree 100% re: getting burned or going somewhere, and haven't been able to find a leak. I would think losing that much oil, the whole under carriage would be black with oil but it isn't.

 

Thank you for your time and suggestion, I'll get both done for sure! I noticed you're in PA, I have Two daughters who live in Annville (Im in UT). Small world

 

Yup oil's gotta be going somewhere if not leaking out. Sounds like head gasket but ya gotta do a compression or leakdown test.

Quick tests you can do at home....
-Do you get white or blueish smoke out of the exhaust? Does it smell sweet?
-Pull the dip stick, does the oil look like chocolate milk?
-If no, with the radiator/coolant cool enough to take the radiator cap off, does the coolant look like chocolate milk?
-If no, with the radiator cap off & the radiator topped off, while peeking through the bottom of the hood or have some one watch, start the engine, when the engine fires up does coolant shoot out of the radiator?

If yes, blow head gasket.

 

Awesome, thank you so much! I'll definitely give this a try as well!

 

If it is drinking a quart of oil every 100 miles, then I understand why you had to put a cat on it and O2 sensors.

 

If that year has an egr valve....your destroying that valve....clogged it will cause truck to run ruff.....

My guess would be you scored cylinder one with a stuck oil ring......
that or a major head gasket leak is only thing that would be that veracious...
or valve guide seal crumble......

 

I got through there at least once a week when I still worked on 934 or 422