Quick help with 1985 Century

[turbojimmy]

Hi all,

My wife's elderly aunt has a 1985 Century with 58k miles on it. For some reason she's been paying the same hack mechanic for the past 20+ years to work on it. She won't let me touch it. Despite the low mileage the car is in rough shape, but she recently spent way more than the car is worth to have this guy replace the head gasket on it. It's an I4.

The mechanic finally retired and I have permission to work on the car. I was over there today and the car wouldn't start. It had the following codes stored: 13, 21, 22, 33 and 45. Basically every sensor under the hood (O2, TPS and MAP). Apparently it's been doing this for a while because the O2 sensor and TPS are new. MAP looks stock - that would be a 2-bar right?

I unhooked the ECM and plugged it back in. The car fired up immediately. The SES light was flashing fast, then slow, then went out. Every time I give it gas the SES light flashes slowly and then stops when I let it return to idle. It also has a nasty stumble I'm thinking that the problem is either:

- misadjusted TPS
- bad MAP
- the guy forgot a ground when he had the engine apart

Anyone run into this before? I'm heading back over there with a voltmeter and some WD40 to clean up the connections.

TIA,
Jim

 

[turbojimmy]

I was just reading the diagnostics for the 02 sensor and realized I did something stupid, but it might shed some light on the problem.

The reason the SES light was flashing was because I forgot to take the paper clip out! It's still in diagnostic mode. But, it fired right up in diagnostic mode so does this tell me anything????

Thanks,
Jim

 

[turbojimmy]

Well, here's how it went.

I paid $26.95 for AlldataDIY access to the service manuals. It was worth every penny. According to the manual, the TPS is critical to other engine functions. It went through the diagnostic procedure and pointed out that the ECM will also set a 22 code (TPS low) to let you know that the wiring and ECM is working fine. It simulates a low condition to make sure it can see the low voltage. This eliminates the wiring and ECM as a possibility and puts the blame squarely on the TPS itself.

The TPS was 'new', but the hack mechanic must've found it laying around. He had bent the tab (not adjustable like our cars) to get the voltage in the right range at idle, but when it swept up and down it was out of range. The bad TPS readings caused all the other codes. I popped in a new TPS ($40) and it fixed it right up.

I felt kind of bad because this lady sits around her assisted living facility all day long and doesn't talk to anyone. She's paranoid schizophrenic and won't take her medicine, so she's tough to get along with and has alienated anyone she has come into contact with except for a few family members. Nevertheless she watched me the whole time and clearly understands what I did, why I did it and why it works now. I explained everything I did every step of the way. Hopefully she trusts me enough now to take care of the car.

So she sees people walk through walls, come out of the TV and steal her stuff, and thinks that the ocean is at the edge of her neighborhood (it's not). She wanted to go for hamburgers but I really was out of time. I made 3 trips out there today, 20-mins each way, to get parts and tools. She was disappointed that I couldn't stay, but relieved that she can now go to the doctor's tomorrow. She's also obsessive compulsive. I'm sure she went to Wal*Mart after I left to buy an air cleaner. I told her it was fine, but she thinks it's dirty.

Oh well, it sucked up my Sunday but it's nice to be appreciated.

Jim

 

[gunslinger]

So she sees people walk through walls, come out of the TV and steal her stuff, and thinks that the ocean is at the edge of her neighborhood (it's not).

No offence intended...but WTF is she doing driving???!!

 

[turbojimmy]

No offence intended...but WTF is she doing driving???!!

Believe it or not, she's okay driving. She drives a little slow, but a lot of old people do. Otherwise she's fine.

I don't think she should be living alone, but they can't take her out forcibly.

Jim