The woman owns a PT cruiser. Recently her oil pressure light started coming on just as she hit her brakes. It has all of 55K miles. After some searching, this seems to be a common issue with PT's. It seems there are 3 scenarios at hand here. 1. The pressure sending unit is bad or going 2. The oil pump itself is bad or going 3. There is a "sludge" issue
Has anyone had experience with this? I did some searching here and there and seems the 1st plan is to remove the sending unit and attach a gauge to read the pressure at idle and 3K rpm. That'll help to determine 1 or 2. Any ideas or thoughts?
Yes. It was checked and then completely changed. The issue has only happened once since the oil change. She had 2500 on the prev. oil change and it was still full at that point so I ruled out oil being burned.
I just had this happen on the way home tonight. It only happened once, but it freaked me out. I was in second, at like 1200rpm or so. I tapped the brakes, and the oil light went on for a split second. I think maybe the RPM's dropped a little too low and the engine was about to stall out.
She's got an autotragic. I did some more reading and found out the sensor triggers when the psi reads between 2 and 4. Normal seems to be 7psi at idle. I need to pull the sensor and manually test the pressure at idle and with the tranny in drive with the brake applied. That condition is the only time her oil light comes on. It would seem that would be a high load moment, but I'm going to have her do the same with it in reverse. I'm holding out on blame until I can test the pressure.
Registered: 10/09/02
Posts: 6364
Loc: Milwaukee, WI
An odd guess would be the throttle posistion sensor...it may be that when she puts on the brake, she's just lifting her foot off the gas. Car tries to return to an idle setting with regards to the throttle...with a bad tps, it'll tend to stall out, but only occassionally/randomly. If the rpm's are dropping much lower than the factory idle speed (~600rpm), it'll trip the oil pressure sensor.
Have you run an obd scan? I'd start there...
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It did throw a cam position sensor code and a local shop replaced it last week. The only other code I'm aware it has thrown was a random missfire. It still trips the oil light when braking.
There are no problems accelerating. It pretty much only happens when she brakes to a stop. Once it gets still, ding light goes on. I could see how it would only happen while it's in gear and stopped. That's a high amount of load. I wonder if it happens in reverse also. I'm going to throw a manual gauge on it next.