Post your car questions here

[JustTheFacts]

Does it harm a car to keep the engine on while fueling?

Sent from my DROID RAZR

no, of course not. well I mean, it could hurt the car if gas fumes caused an explosion, that probably wouldn't be too good for the car lol

What's the deal with a pressurized tank, if that is what it is called. I left my gas cap a little loose on the S2000 and the engine light came on after a while.

That is the EVAP system, which's entire purpose is to capture stray gas fumes and return them to the tank. In order to work the system must be pressurized.

The computer is constantly monitoring the EVAP system and when it detects a leak it triggers a code which turns on the check engine light.

Actually that's not quite right. The computer actually has to register several such codes before it triggers a light. That's why it won't come on if you leave the car running while you refill for example. It takes multiple instances in a row to turn the light on.

 

[L.K.Eder]

where did i park my car?

 

[JustTheFacts]

where did i park my car?

Dude!!!

 

[Warrior102]

no , actually power went up considerably. the 1967 289 with a 4 barrel carburetor had 210 HP (except of course for the K code 271 HP HiPo model) the 1968 302 had 251 HP

Interesting. Never knew that.
I saw '68 as a huge "fuck up" for the big 3 -- always considered '67 as the last of the best

 

[JustTheFacts]

no , actually power went up considerably. the 1967 289 with a 4 barrel carburetor had 210 HP (except of course for the K code 271 HP HiPo model) the 1968 302 had 251 HP

Interesting. Never knew that.
I saw '68 as a huge "fuck up" for the big 3 -- always considered '67 as the last of the best

68 had some bad ass cars from each of the big 3. Not sure I'd consider it a fuck up. 72 was the beginning of the end for the big 3 IMO.

 

[Papawx3]

Here's a question for you:
Never mind. I got into this hoping to get an answer to a question I have about my truck. But then I find out that the guy that I hoped would answer my question has been banned.
That's just great....:

 

[TNHarley]

Someone might can help you. What is your problem?

 

[Desperado]

Here's a question for you:
Never mind. I got into this hoping to get an answer to a question I have about my truck. But then I find out that the guy that I hoped would answer my question has been banned.
That's just great....:

Boy that sucks.....
Give it a shot any way.

 

[ConHog]

Here's a question for you:
Never mind. I got into this hoping to get an answer to a question I have about my truck. But then I find out that the guy that I hoped would answer my question has been banned.
That's just great....:

ask your question bruh

 

[Sunni Man]

^^^ Same guy.....just new identity........

 

[Papawx3]

OK, here it is.
I have a 1998 Ford F-150 Super Cab pickup with a 4.2L V6 and just over 155K miles on it. I bought this truck used last year from a private owner.
A couple of months ago I started having a lot of trouble starting it. It hadn't been serviced in quite a while so I took it to my mechanic's (ASE certified) shop for a tune-up. He did that and he also cleaned out the throttle body that he said was really 'gunked up'. Since then, the problem has gotten a lot worse. The engine turns over, and over for several minutes before it finally fires. I was thinking that the fuel pump is failing. Except that once it fires and starts, everything runs fine. I can drive it all day long without a problem. I can cut it off, and as long as it's only for a few minutes, it will restart without any problems. But when I leave it overnight, I can bet on it taking an awful long time to start in the morning. I'm all for getting it fixed, but I'd like to fix it the first time. I'm in no mood or financial position to repeatedly replace parts until I find the real problem.
Any suggestions?

 

[TNHarley]

My z-71 was like that. I replaced the starter and it fixed it..
But it could also be the crank or coolent sensor. You could get the starter checked before buying one, you might could get the others checked out as well, but IDK for sure..

 

[Zona]

I'm ASE certified Master Tech , and in an effort to try to clean up the image some of you all seem to have about "mechanics" if you post a question here you will know that any answer I give you will be free of motivation to rip you off as you aren't likely to be my customer.

As today's cars are much more sophisticated than their predecessors one really needs seek expert advice before fiddling with anything or trusting their vehicle to someone who may not be qualified just to save a few dollars.

Ask anything I'll do my best to help you. Although obviously diagnostic abilities are limited without having the vehicle in front of me.

Is there any car or truck you would tell others to avoid purchasing because their maintenance is costly or their repairs/troubles are excesy
sive?

yup, BMW's. I have two and love them but if you cant turn a wrench, you are screwed. Great great motors though. Horrible cooling systems.

 

[Sunni Man]

The engine turns over, and over for several minutes before it finally fires.

It's not the starter.

But definitely a fuel problem..........

 

[TNHarley]

The engine turns over, and over for several minutes before it finally fires.

It's not the starter.

But definitely a fuel problem..........

It fixed my truck. Mine would lag for 4-5 seconds, replaced that and back to normal

 

[ConHog]

OK, here it is.
I have a 1998 Ford F-150 Super Cab pickup with a 4.2L V6 and just over 155K miles on it. I bought this truck used last year from a private owner.
A couple of months ago I started having a lot of trouble starting it. It hadn't been serviced in quite a while so I took it to my mechanic's (ASE certified) shop for a tune-up. He did that and he also cleaned out the throttle body that he said was really 'gunked up'. Since then, the problem has gotten a lot worse. The engine turns over, and over for several minutes before it finally fires. I was thinking that the fuel pump is failing. Except that once it fires and starts, everything runs fine. I can drive it all day long without a problem. I can cut it off, and as long as it's only for a few minutes, it will restart without any problems. But when I leave it overnight, I can bet on it taking an awful long time to start in the morning. I'm all for getting it fixed, but I'd like to fix it the first time. I'm in no mood or financial position to repeatedly replace parts until I find the real problem.
Any suggestions?

My initial thought it Crankshaft Position Sensor

Without access to a datastream from a scanner that's just a fairly educated opinion, but no guarantees.

The good news is that sensor is about $30 and fairly easy to change. Not more than an hour labor.

 

[Sunni Man]

My initial thought it Crankshaft Position Sensor

Without access to a datastream from a scanner that's just a fairly educated opinion, but no guarantees.

The good news is that sensor is about $30 and fairly easy to change. Not more than an hour labor.

If that's the problem....then why would it eventually fire up and start?

And then keep starting for the rest of the day after it warmed up?

 

[ConHog]

My initial thought it Crankshaft Position Sensor

Without access to a datastream from a scanner that's just a fairly educated opinion, but no guarantees.

The good news is that sensor is about $30 and fairly easy to change. Not more than an hour labor.

If that's the problem....then why would it eventually fire up and start?

And then keep starting for the rest of the day after it warmed up?

Because the way the system works, and this is pretty standard anymore is that the fuel injectors won't fire unless and until the crankshaft position sensor sends a go signal to the engine computer and the engine computer relays that signal to the fuel injectors.

So what happens is that when a CPS starts failing it begins to randomly not send the appropriate signal and so the vehicle will crank but not turn over. Eventually it will not send the signal at all.

His technician can easily verify this either with a scanner by simply going into the datastream and checking the CPS voltate or by using a multimeter to manually test the voltage at the CPS. It' a simple 2 wire sensor. One wire has a 5V reference and is always hot , the other is the wire that signals the ECU that engine has been cranked over, it should have around 5 volts when cranking , if it's < 3.6V the sensor is definitely bad.

99 out of 100 times it is this sensor. No guarantees diagnosing it over the internet. But that' my thought.

 

[Papawx3]

My initial thought it Crankshaft Position Sensor

Without access to a datastream from a scanner that's just a fairly educated opinion, but no guarantees.

The good news is that sensor is about $30 and fairly easy to change. Not more than an hour labor.

If that's the problem....then why would it eventually fire up and start?

And then keep starting for the rest of the day after it warmed up?

Because the way the system works, and this is pretty standard anymore is that the fuel injectors won't fire unless and until the crankshaft position sensor sends a go signal to the engine computer and the engine computer relays that signal to the fuel injectors.

So what happens is that when a CPS starts failing it begins to randomly not send the appropriate signal and so the vehicle will crank but not turn over. Eventually it will not send the signal at all.

His technician can easily verify this either with a scanner by simply going into the datastream and checking the CPS voltate or by using a multimeter to manually test the voltage at the CPS. It' a simple 2 wire sensor. One wire has a 5V reference and is always hot , the other is the wire that signals the ECU that engine has been cranked over, it should have around 5 volts when cranking , if it's < 3.6V the sensor is definitely bad.

99 out of 100 times it is this sensor. No guarantees diagnosing it over the internet. But that' my thought.

I'm an electronic technician by trade and have my own digital multi-meter. Is it something I can check? If so, where is it located and which wires should I check?

Also, I looked up the CPS at Rockauto.com and I can buy the CPS online for about $21.00. I'm willing to buy that if it will cure the problem with my truck.

 

[ConHog]

If that's the problem....then why would it eventually fire up and start?

And then keep starting for the rest of the day after it warmed up?

Because the way the system works, and this is pretty standard anymore is that the fuel injectors won't fire unless and until the crankshaft position sensor sends a go signal to the engine computer and the engine computer relays that signal to the fuel injectors.

So what happens is that when a CPS starts failing it begins to randomly not send the appropriate signal and so the vehicle will crank but not turn over. Eventually it will not send the signal at all.

His technician can easily verify this either with a scanner by simply going into the datastream and checking the CPS voltate or by using a multimeter to manually test the voltage at the CPS. It' a simple 2 wire sensor. One wire has a 5V reference and is always hot , the other is the wire that signals the ECU that engine has been cranked over, it should have around 5 volts when cranking , if it's < 3.6V the sensor is definitely bad.

99 out of 100 times it is this sensor. No guarantees diagnosing it over the internet. But that' my thought.

I'm an electronic technician by trade and have my own digital multi-meter. Is it something I can check? If so, where is it located and which wires should I check?

Yes , you could test it and probably even change it if need be by yourself.

The crankshaft position sensor is located on the lower right front of the engine. Down by the crankshaft pulley itself.

here is a generic sensor, they all look similar.

there are two wires. Can't remember for sure, but I think they are Dark Blue and the other is Gray. I can look it up if you need me to.

The Gray I believe is the reference wire. Should have 5V at all times, the other is the signal that should put out around 5V when the engine is cranked.

If it needs to be changed, its a simple unplug electrical connector, remove two 10mm bolts and gently pry sensor out of engine.

Reverse to install, but be very careful not to scuff the end of the sensor. There may be a felt pad on the end of it, do NOT remove that pad, it is a spacer that must be there if it came from the factory with one.

If you do it yourself be aware that for the first 20 miles or so after replacement the truck will drive like shit until the computer can do a relearn.


I can't promise anything , I mean I'm diagnosing without even seeing the car you know, but I'm fairly confident it is the Crankshaft sensor.