JCC

Here’s my situation,

I live in California and took my 2001 Malibu in for its bi-annual smog test. I had to take it to a “test only” facility that can’t do any repairs. My car passed the emissions part of the test with flying colors but failed the OBD II portion of the test. Because of that it failed the test.

The tech asked if I disconnected the battery recently and I hadn't so I told him no. He told me that my car wasn’t in ready mode or something like that. He said I could do a drive cycle and it would reset it. I did and it didn't.

Here’s what I think the problem might be. My water temp gauge doesn’t work all of the time. I’ve replaced the coolant temp sensor withan aftermarket one and a dealer one and I’m having the same problem. When I drive my car home from work in the afternoon when it’s warm outside the gauge works fine. When I go to work in the morning when its cold the gauge works for about 10 of 15 miles then it stops working and the needle falls down like it’s stone cold. I drive more miles with it working than not but I don’t drive enough miles for the check engine light to trip though. I've checked for fault codes with my scanner but it doesn't show any fault codes.

Would this keep the OBD2 system from making ready mode? If so, what could I check to fix it since I’ve replaced the coolant temp sensor twice now to no avail?
<o</o
<oJCC</o

in2pro

Welcome to the forum...

Do you know which monitors are not being met or not ready, all or ?

Make sure that when you are reading them that you are not also clearing or resetting any codes, as that will also reset all drive monitors....

JCC

I think the tech said it was the CAT test and the EVA test.

Here's what I did so far. I disconnected the battery for 3 hours yesterday while I was at work and I reconnected it and drove home and the temp gauge worked fine.

This morning while driving in I was getting close to the 10 mile mark and I saw my temp gauge was at 1/4. I got off the freeway and drove surface streets and my temp gauge went up to normal. I got back on the freeway and my temp gauge started dropping below the half way point so I got back off the freeway.While driving the surface streets the temp went back up to normal so I drove them most of the way into work. The temp gauge registered the whole way.

When I got to work I hooked up my OBD2 scanner and under the I/M Monitor Status the only thing still flashing is the EVA icon with a yellow light. If I can get that light to turn off I can pass the smog test and then focus on the fix.

in2pro

I would avoid disconnecting the battery, as that is only going to prolong the agony so to speak...
Keep in mind the gauge not working or responding correctly doesn't mean the ECM is seeing that same temp fluctuation...the sensor could be working fine, it could be that gauge is the problem....
You need a scanner that can tell you what the real time temperature reading is....
You may need to drive 40 + miles and do 3 or 4 key on, key off cycles... basically, disregard the gauge for now and drive a week and check your monitors...

JCC

Thanks, I'll give that a try.

I've had an aftermarket locking gas cap on my car for years now but I just put the stock one back on hoping it has a tighter seal.

in2pro

Ahh.. so you are getting an EVAP failure also? those can be more of a pain to troubleshoot...rarely is it the gas cap, but since you changed yours its a possibility... it's usually the vent valve or the canister... if you tend to over fill your gas tank or top off after the first click, this can damage the EVAP system by overloading it with liquid fuel...

JCC

I do top off after the first click. My car has 250,000 miles on it and right now I can't afford to get another one.

Can the vent valve and canister be cleaned or dried or would they need to be replaced?

in2pro

I don't want to tell you to replace something solely based on what we have exchanged in the forum... but if you are getting EVAP codes it usually means something has failed in that system, and the items associated with that system are vent valve, purge valve or solenoid, canister and an assortment of hoses...
Without the tech2 tool to activate some of those systems, its going to be hit or miss on your part, but I could guess that you want to fix it yourself if at all possible

JCC

I did my best to do 2 driving cycles, which are nearly impossible in southern California, but my OBD2 scanner still showed a yellow light in the I/M Moniter Status with the EVA icon still flashing.

So I went to my local DMV and wanted to get an extended moving permit but they wanted to charge me $50 for a 2 month moving permit. I settled for a free 2 day moving permit.

But when I got to work this morning I checked and nothing was flashing ang the light was green. I blurted out in my car, Thank you Lord! I'll be going to my local test only smog station after work and finishing what was started the other day.

Thanks for your help and suggestions in2pro.

in2pro

You are welcome and thank you taking the time to follow up !