1997 Subaru running rich?

My daughter has a 1997 Subaru wagon and has just dumped $800 into it but there is still a problem. First it was a new coil then a camshaft position sensor then a knock sensor and then a catalytic converter. The engine is a 2.5 I believe. Well now you can barely get it over 40 mph and the catalytic converter is glowing red hot after a couple minutes. This is a sign of an engine running rich right? Any suggestions as to what I should look at next? Thank you in advance.

That is an engine running mega-rich, and that brand new converter isn’t going to live long if it’s subjected to much more of that. Surely the check engine light is on, and if so, she needs to have someone (eg AutoZone) hook up to it and figure out what sort of information the computer has stored. Bring that info back here and we can maybe point you in a direction.

A few easy things to do, first: Use a MAF (Mass Air Flow) sensor spray cleaner; then, an intake tract cleaner on the idle air control (iac) valve, and the throttle plate and bore. You only need to remove the large, black, plastic tube to clean these parts. The spark plugs are fouled (yes, again) from the rich running. Change’em. Have the scan done. Bring codes, here.

Yes and the plugs are new too and there is a check engine light. I will try your suggestions and let you know what the codes are. Thank you!

When a fuel injector wears out, it can do that. Yours is probably stuck wide open and just pours the fuel in there. I bet the car starts really good. Junkyard shopping might help. The fuel injectors aren’t too big and most come out easily. The one for an 87 Tempo cost me $100 new back in 1991. Ahh for the simpler times.

Ah tempo’s, the cars that made people think domestics only lasted 100k. :slight_smile:

Consider addint a can of sea foam to gas when 8 gallion or less . it is a great cleaner- our taurus runnin to rich and the seafoam corrected the issue. Hope it works for you…

One fairly common problem is the coolant temperature sensor for the ECU. This is different than the one for the dash gauge and has two leads going to it. It can fail and make the ECU think that the engine is cold while the engine is really at operating temperature. To check it, you can watch for voltage changes across the sensor leads as the engine warms up. I think the sensor is on the passenger side near the front or middle of the engine.

Hello and thanks for the help.
There are 5 codes. A misfire on all four cylinders and a "Knock sensor 1 circuit (Bank 1).
Those are the codes. Does a coolant temp sensor through a code if there is a problem?
What do you think ? Anything is helpful. I have attached a text file report from my code reader. Maybe this will be helpful?
Thanks much!

The coolant sensor can look ok to the ECU but still be bad and cause this this kind of trouble. I would check it out as it is very likely to be the trouble.

The red hot catalytic converter is not necessarily because of a rich running engine. The richness can cause the engine to misfire but the misfire is the reason the CC is overheating. There are a lot of other causes for misfire. The most likely suspect is ignition problems or maybe even overly rich or lean conditions. Are you getting black smoke out the tail pipe? Is the tail pipe black with carbon?

As others have said get the missing fixed ASAP or you will need a new CC soon.

Hello and thank you.
No black smoke or carbon at the tailpipe. Yes it is not drivable for this reason. I will look at a possible ignition problem.
thanks