What causes erratic Ck Eng light related to a leaking “tight” gas cap? It comes on and goes off per daily trips basically (T4R 07 V6 2WD 53,000mi). Could it be related to Tx 90s + Heat? Could it be due to only 2-3 10 mile trips a week? The cap passed and still has a good Full O-ring Shape vs failing from over tighten and flattened some initially. The light stayed off solid for 6 months + in cooler weather.
What causes erratic Ck Eng light related to a leaking “tight” gas cap?
- Thread starter jow
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BlackWorksInc
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What DTCs are you getting?
http://www.toyota-4runner.org/4th-gen-t4rs/151487-check-engine-trac-vsc-read-me.html
http://www.toyota-4runner.org/4th-gen-t4rs/151487-check-engine-trac-vsc-read-me.html
You have a slight leak. Gas has a low vapor point, and at summer temps goes to air quickly. This both wastes fuel and hurts environment, hence why your car reports it.
In cold weather, there isn't as strong a vapor pressure pushing out.
So, it would appear you have a slight leak in your tank or cap or possibly vapor return line from tank to engine.
My theory anyway.
In cold weather, there isn't as strong a vapor pressure pushing out.
So, it would appear you have a slight leak in your tank or cap or possibly vapor return line from tank to engine.
My theory anyway.
Thanks BlackWorksInc! I know your point and experienced a good diagnostic scan of many many items (passed/failed) vs the Auto Store’s. This had to be the computer/scanner that can retrieve history from the T4R computer.
1. The O’Rreilly’s Auto scanner w/n show a code as the Ck Eng light was on and off as I got there.
2. A State Inspection Tech told me I needed a large scanner that could ck history stored.
3. A Toyota Specialist close by had the needed scanner and scanned the complete sys and went back to get the code of the failed item. I d/n get the # but he said it's a bad stop light switch causing the Ck Eng/ABS light (from the code # on his PC).
4. I braced for the charge but there was no charge and he will replace the switch next week. I feel this time consuming test is the 129.00 Diagnostic I heard Dealers would run X codes.
1. The O’Rreilly’s Auto scanner w/n show a code as the Ck Eng light was on and off as I got there.
2. A State Inspection Tech told me I needed a large scanner that could ck history stored.
3. A Toyota Specialist close by had the needed scanner and scanned the complete sys and went back to get the code of the failed item. I d/n get the # but he said it's a bad stop light switch causing the Ck Eng/ABS light (from the code # on his PC).
4. I braced for the charge but there was no charge and he will replace the switch next week. I feel this time consuming test is the 129.00 Diagnostic I heard Dealers would run X codes.
BlackWorksInc
New member
Sounds like the DTC was stored mainly on the ABS side of the vehicle, which is why you needed a scanner that could speak to the ABS module (it lives on an isolated network from the OBDII system and only communicates through the ECM.) Though I don't recall that setting an MIL usually (not unlikely though, its just been a while since I had a stop lamp circuit DTC come in the shop.)
Most dealerships charge a flat diagnostic fee to pull codes and determine the issue within about .8hrs of labor (if its more than that to do additional testing, the technicians will talk to the service writer to try and sell additional time), usually we end up just pulling the codes, P&A the part, and quote labor and such. But other times we (royal we including all technicians) actually have to get off our lazy butts and do diagnostic work.
Most dealerships charge a flat diagnostic fee to pull codes and determine the issue within about .8hrs of labor (if its more than that to do additional testing, the technicians will talk to the service writer to try and sell additional time), usually we end up just pulling the codes, P&A the part, and quote labor and such. But other times we (royal we including all technicians) actually have to get off our lazy butts and do diagnostic work.
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