No check engine light (1 Viewer)

[florida95fzj]

I'll admit I mishandled the pre-purchase inspection of my LC80. I did not connect a code reader to the car before buying it and ignored some other issues that I knew would take some work to fix. Nothing catastrophic - just expensive.

So, I am getting 8 MPG on a totally stock and empty LC80. OEM tire sizes and no accessories. I put a code reader on today and have four codes for both O2 sensors and one for knock sensor #2.

Shouldn't the check engine light be on with five codes of these types?

I've heard of car sellers removing the bulb when selling a car and I don't see a CEL light test itself when starting the car, assuming the LC80 does that.

Let's hope the O2 sensors haven't been bad for a long time and have clogged up my cat.


Also -

Another post here says I need 89465-69085 and 89465-69105 (rear). I can't find the rear one anywhere except Impex. Even Partsouq says "not available". My local dealer's parts website says 89465-69115 is the replacement but describes it as 1992-1995. No other parts site says this.

Although, I can't find any NLA references for 89465-69105 in the sticky thread. Lots of NLA threads for ODB1 trucks but not the 1995-1997s.

Joey from Wits End sells the Denso. His website says "not available" but he said he would have more coming in a few days. I'll probably just go this route and he even includes gaskets/nuts.

FYI to others in case the OEM rear sensor is really NLA. I don't have the experience to figure that out.

 

[florida95fzj]

93,000 miles. I haven't put more than 200 or so miles so far.

Yeah, no symptoms of a bad cat from what I can tell.

 

[bigredmachine]

Shouldn't the check engine light be on with five codes of these types?

not necessarily if their history codes, history codes indicate that there was a problem and that problem was either corrected and the codes werent cleared or its an intermittent issue that is not causing a current code at this time.

from what your describing i would say that yes you should have a mil.

I don't see a CEL light test itself when starting the car

thats a problemm, mil should come on every time the vehicle is stated or key is put into the on position. its easy enough to pull the combo meter to see if theres a bulb in the socket position and them move on with diag from there as to why the mil is not working

 

[florida95fzj]

I'll test out that MIL bulb.

I'll also check for vacuum leaks like @YardSale2 mentioned and see if the ODB2 can give me info on fuel trim. From what I can tell, 8 MPG is pretty bad for a stock LC80.

 

[bigredmachine]

8 mpg is pretty bad, i was getting 9mpg in the winter before i replaced the exhaust. it was so rusted away i was basically running open down pipes and the o2 sensors werent doing anything. on that note how is the exhaust system, having leaks before the o2 sensors can also give false readings

 

[florida95fzj]

on that note how is the exhaust system, having leaks before the o2 sensors can also give false readings

Actually I need to look at that closer. I removed the heat shields to get access to the thermostat bolt and the exhaust manifold didn't look that great but I didn't notice any obvious cracks.

 

[florida95fzj]

Any crack would be obvious, you would hear it while the engine is running.

Edit: No offense but people in Michigan will have a rotten exhaust before someone in Florida, due to salting the roads.

I have to say that my 1FZ-FE is pretty loud. I was surprised it was much louder than the 1GR-FE in my 4Runner.

 

[florida95fzj]

I'm willing to eat some crow, although I prefer possum, smothered in mustard and MSG.

We're troubleshooting over the internet, 93k miles in Florida, I'm imagining some garage queen that Tony Montana's wife used to pickup her kids from day care. Then off to their 52' Hatteras to go vacation in the Bahamas, whilst being waxed at the marina.

Not a garage queen for sure. The PO had the truck for all but the first year or two. I think he is in his 70s now and this was his wife's car in later years, he said. I've only had it a month or two.

I think the most expensive screw up is the paint job. It looks like select parts of the car got the rattle can treatment likely with no prep at all. Otherwise, it's just neglected maintenance and aftermarket parts that in some cases aren't correct.

 

[florida95fzj]

First off, does the antenna retract? If not, light it on fire!

Nope, broken.

Just BS'ing, she looks like a very nice 80. Not many 70 year olds paint their wheels for their wife, I'm guessing the door handles were also painted... although I've never owned an emerald green 80, I think they should be color matched. Is that the rattle can part? I like her! Good platform! Maybe a transfercase leak/transmission? Figure out the troublesome codes and enjoy her!

Yeah, I think he did that a while back when it was "his" car. Even the spare wheel is painted. Well, assuming he disconnected the MIL bulb, I can't believe anything he told me but I am skeptical of everything regardless. The only thing that seems true is he didn't use it as an off-road truck. Especially with these China-bomb tires.

The rattle can was used on the hood, hatch, and around the rearmost windows. There's black drip marks around them and pretty much everywhere he painted.

Leaks? Distributor o-ring, power steering. There is something caked on the transmission pan but nothing is leaking on the driveway at this point from any part of the car. I haven't had a chance to look at the leaks yet. Just got the coolant sludge handled and got the temp down.

 

[elhombre]

I would suggest you pull each spark plug and have a look. Do a compressible test on each cylinder with the engine warmed up. You need to find out what you are working with before dumping a bunch of money into it.

The fact that someone disabled the check engine light is exactly what you can guess it means. As a general rule of thumb, get a reader and erase the codes, and see what comes back on after a drive.

And as mentioned, a leaking exhaust will throw O2 codes. There is also a bunch of reasons O2 sensors will cause the computer to set a code. They are the last sensors the computer sees, and if something up stream is not right, the computer will see it as problem with the signal from the O2 sensor.

 

[florida95fzj]

Looks like the upstream O2 sensor is most likely good. Voltage looks as you'd expect when the truck is running on sensor 1. It averages around .4V going up and down as normal.

However, the ECU was calling for negative short term fuel trim as high as -20% only when the RPMs are high. Short term fuel trim is fine at idle.

Going to break out the FSM and going to capture some data while driving.

The downstream sensor was either 0V (probably not hot enough yet) or steady around .05V.

 

[florida95fzj]

I could not replicate that odd behavior where the ECU was reducing fuel by -20%. During the test drive my fuel trim was really good for such an old engine. The ECU was not adding excess fuel. O2 sensor #1 was showing good data as well.

I am going to continue my baselining and check on this after I am done.

 

[lp2k]

your rig looks fine @florida95fzj - i guess the paint is noticeable when your closer up. or my eyes are getting old lol

 

[florida95fzj]

your rig looks fine @florida95fzj - i guess the paint is noticeable when your closer up. or my eyes are getting old lol

Yeah that’s the best side . I’ve read your painting post. Excellent write up. My hood and hatch could use that treatment. One day.