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Old 02-03-2014, 05:07 PM   #21
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cam wont make it not start. and this car i looked at rpm while cranking which i believe comes from the crank sensor. yep pretty hard to trouble shoot a problem that has occurred twice since he he has had it and runs perfect at other times. it get 32 mpg and everything on live data looks fine, even when it wouldnt start
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Old 02-03-2014, 05:20 PM   #22
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cam wont make it not start. and this car i looked at rpm while cranking which i believe comes from the crank sensor. yep pretty hard to trouble shoot a problem that has occurred twice since he he has had it and runs perfect at other times. it get 32 mpg and everything on live data looks fine, even when it wouldnt start
This is correct a bad cam sensor will let the engine run but it will have an extended crank and set a check engine light. With a intermittent problem like this it could be a ton of different causes. If it is the crank sensor it won't set any codes which is stupid because you would think if the PCM see a signal from the cam sensor and not the crank sensor it would set a fault. My sisters 02 park ave had a no start/ very extended crank and it turned out to have a pin hole in the FPR causing a flood issue.
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Old 02-03-2014, 05:59 PM   #23
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cam wont make it not start. and this car i looked at rpm while cranking which i believe comes from the crank sensor. yep pretty hard to trouble shoot a problem that has occurred twice since he he has had it and runs perfect at other times. it get 32 mpg and everything on live data looks fine, even when it wouldnt start
Mine doesn't have a cam sensor, so I lumped it together with the CPS. Makes sense and good to know. I haven't driven mine for about 3 weeks 'cause I don't trust it now. When the problem started, I would need to depress the gas a tiny bit and it would start right up and run fine during the trips. Only happened occasionally. Now, more often than not, I have to press the pedal to the floor before it starts. TPS reading is 'bout perfect and consistently so.

I started it a few minutes ago and it started on it'* own the first time and idled good. Let it run about 4 mins. and shut it off. Had to floor the pedal to get it started again. When I did this last week, I had to floor the pedal and crank it a while before it started. Also, last week I let the engine get warm while charging the battery and the idle would vary. It would run normal RPM for a minute, then idle faster a minute, then back to normal for a minute and faster for a minute. It did this for about twenty minutes or so. Starting to creep me out.
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Old 02-04-2014, 07:25 AM   #24
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obd1 cars are like that if you let the battery run low all your learned values reset and take a while to get back to normal. as far as the not starting i would try doing half throttle when it wont start because full throttle is clear flood mode and it shuts off the injectors, if it starts better this why i am thinking its just a iac issue, if your tps looks fine. if you still have to go full throttle some how its flooding
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Old 02-04-2014, 07:27 AM   #25
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This is correct a bad cam sensor will let the engine run but it will have an extended crank and set a check engine light. With a intermittent problem like this it could be a ton of different causes. If it is the crank sensor it won't set any codes which is stupid because you would think if the PCM see a signal from the cam sensor and not the crank sensor it would set a fault. My sisters 02 park ave had a no start/ very extended crank and it turned out to have a pin hole in the FPR causing a flood issue.
still have to check this he has not brought the car over. he usually drives his truck when he isnt going to work, and like i said he is not the type to try preventative measures. when it was not starting here the first time, the first thing i did was put a pressure gauge on it and that seemed fine
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Old 02-04-2014, 01:09 PM   #26
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This is a tough one to figure out when you don't have access to the car and it'* very intermittent. I'll be interested to see what the problem was.

My battery was never low enough to reset the ECM. I'm thinking I partly have a moisture/gas issue to remedy before I do anymore troubleshooting. NAPA was out of the Thermo-aid the last time I checked, so I eventually forgot about it. Waiting on a little better weather to get into it too much.
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Old 04-07-2014, 09:53 AM   #27
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the thing stalled a couple more times lately and i was working on the bearings and he said its got the gas cap light again, so i hooked up the scanner to it to see if there were any other evap codes. it had the evap plus two o2 codes and 1 crank position sensor code. so that sort of backs up the crank sensor being the fault for the stalling at least. replacing it is a pain on these, so i havent done it yet
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Old 04-07-2014, 02:48 PM   #28
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I'm glad to hear that something finally turned up. Whew! You thinking that the O2 codes are related to the CPS not functioning?

I'm still using the weather as an excuse for my CPS. I bought it a couple months ago, but been taking the easy way out with the wife'* car. It'* about time to do it.

I'll be watching JW...
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Old 04-07-2014, 06:57 PM   #29
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i think the o2'* are a separate issues, i have had o2'* go on other vehicles and crank sensors and normally o2'* just make it run bad(which is starting to happen on this car). when its just the crank sensor it runs fine.
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Old 04-21-2014, 06:45 PM   #30
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I finally replaced my CPS today. It seems to have fixed the starting problem. After a dozen, or so, cold and hot restarts, it starts normally now.

I ran mine without a O2 sensor for a while (couldn't get the old one out). Now fixed thanks to a torch.
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