Corolla running badly?

[jfridge92]

Hey guys, this is my first post here so I apologize in advance if I have repeated a topic, although I don't believe i have. The information related to this that I've searched on here hasn't really helped as far as directly addressing the problem, so here's a summary. I drive a Buick and am usually on forums for that, so my knowledge on Toyota's isn't quite as good, but I'm sure some here can be of assistance.

So here's whats going on, and what has/is going to be done: *Note that this is the girlfriend's car and I don't drive it much, so I can't say how bad it is compared to how it was when it was in top shape, but there's definitely something up.

The problem: The car has a slow startup, not like the engine cranks over for a while, but as soon as it fires, which is at the flick of the key, it idles up really slow, from like 300 or so, and it takes it a second to get up to proper speed, which I believe is around 900 or so? I do remember in the past that the car started no problem, so this is definitely one thing I've noticed. Also, she's been complaining about it feeling like it wants to stall on her when she's driving, and that it has no power anymore and does nothing when she gives it gas. I drove it the other day to see, and it runs like crap. It doesn't sputter or anything, but just has no power and does exactly what she says, acts like it's just going to die on you even though it doesn't. When you floor it all the way, it takes forever to get any speed at all, and even though it's a small engine (I'm used to driving a V6 modified with 250hp or so, so the 1.8 is a little slow to me, but nothing wrong with that ), it should have more power than that.


So here's what's been done: New NGK spark plugs like 2 months ago, brand new battery last week (For slow start), tested the altenator and starter (both good), replaced air filter, replaced belt tensioner (it was bad a while ago), and a few other little things that haven't helped.

I'm going to clean the MAF and throttle body tomorrow morning after class, so maybe that will help somewhat (The MAF wires are black from buildup!).
I've been told by a mechanic friend to check the fuel pressure, but I'll have to rent a tester for that, and since it's not misfiring or throwing any codes, I'm pretty sure the plugs and coils aren't an issue and it's getting spark. The fuel filter is in tank on the pump assembly, so I'm not going to even try that for now unless the fuel pressure is shotty, as the tank would have to come out to change the pump, filter, and regulator anyway.

Aside from this, does anyone have any other suggestions? I thought about putting it in first and flooring it (not too much though) to see if it has any power loss to rule out a transmission lock issue (mechanic friend mentioned doing that as well) but I'm not sure as to what else could be causing this. It could be anywhere from fuel, TPS, IAC, IAT, MAF, you name it. I'm just looking to see if anyone can help narrow it down a little easier so I don't just go off on a wild goose chase.



Sorry for the long post, and thanks so much in advance for the help, and for the awesome forum resources!

- Joseph

[fishexpo101]

Make sure fluid levels on spot on - not too much or too little, especially with motor oil.

Wouldn't be a bad idea to clean out the throttle body, check on the PCV, and all vacuum hoses. If you can, check for vacuum leaks (I'd just hit the vacuum hoses with some spray to temporarily "plug" a leak - see if idle speed surges, indicating a leak at that point - plain water with couple of drops of liquid detergent in a spray bottle works just fine).

How did the plugs look when you replaced them?

Checking fuel pressure is semi-painful. There is no readily accessible fitting available on the car, you'll have to disconnect the fuel hard line running to the fuel rail and insert a T-fitting. Might be able to beg/borrow/buy that SST at the Toyota dealership.

[jfridge92]

Thanks for the quick reply, I always keep the fluids topped. It has the famous oil burning issue, about 3 quarts every 1500 miles or so, so I always watch that for her haha.
As for the plugs, they had a lot of white buildup on them, I can't remember if that's from running too hot, lean, or rich though.

As for the fuel hardline, I'm not sure if I want to tackle splicing into that on my own versus someone who knows more about fuel systems.

When I clean the MAF and TB, I'll spray carb cleaner to see if that will affect idle any.

Hopefully one of those things will fix it, it seems that dirty mafs are a pretty big issue for robbing power on these cars.

*edit* I forgot to mention? I put a new PCV valve in last week

[fishexpo101]

Sounds like a plan. Those white deposits (ash) are from the additives in the oil when it is being burned off in the combustion chamber. Not a problem unless the build up is so severe that it bridges the gap in the plug causing it to misfire. Might be worthwhile to have a new set of plugs to test out.

[jfridge92]

Well, I did everything on my maintenance list, and after cleaning the MAF the car ran noticeably better. Here's the kicker. I got a call 2 days ago from the girlfriend saying she was hearing a strange noise from the car. I told her to bring it by so I can look at it, and what do you know, it came knocking away. So it looks like it's time for a new engine.

[dorkiedoode]

i would've suggested you do a compression test if i found this earlier