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Car Novice Question: Will Autozone Comp Diagnostic give results if no dash lights on?

My car is having an issue where the RPM shots up, but the car doesn't move all the time. If I take my car to Autozone for a computer diagnostic, do you think it will give results without any oil lights being on? Well the question is DOES AUTOZONE comp test give results if there is no lights on?
 
I'm assuming you mean that your dashboard is not showing any "warning" lights (oil pressure, check engine, etc). I'm not an expert on the computer coding, but I believe the computer diagnostics simply read the code that produces the warning light. So I'm afraid that may not be an option. Of course, they don't charge for it, so it wouldn't hurt to give it a try (just your time).

So you're issue is that as you are sitting still, the engine revs up randomly but doesn't go anywhere?
 
Sometimes, the car's computer will throw a code without illuminating a warning light. It's rare, but it happens occasionally, so it'd be worth a look anyway. I doubt you'll find your problem that way however. My first thought is that you might have a vacuum leak somewhere.
 
Some stored trouble codes will not give a MIL(malfunction indicator lamp) aka engine light. Is this when it is trying to shift? Or when trying to move from a stop?
 
I'm assuming you mean that your dashboard is not showing any "warning" lights (oil pressure, check engine, etc). I'm not an expert on the computer coding, but I believe the computer diagnostics simply read the code that produces the warning light. So I'm afraid that may not be an option. Of course, they don't charge for it, so it wouldn't hurt to give it a try (just your time).

So you're issue is that as you are sitting still, the engine revs up randomly but doesn't go anywhere?

Yea it moves, but randomly while im driving and I press the gas the RPM shots up but the mph doesn't go up. I accidentally left the engine oil cap off and alot of engine oil came out, I don't know if that was the start of the issue or what.
 
I wouldn't think that would be the root cause of your problem. Leaving the filler cap off with the engine running would cause oil to leave the engine. There's plenty of moving parts under there that throw oil around inside there. It's like a blender: if you remove the lid while it's on, your milkshake is going to exit the blender real quick like.

It could be a potential idle air control valve or PCV valve issue (if your car has one). Failures of those should throw codes that would put the check engine light on, assuming that your check engine light works.

EDIT: does this happen while you're idle/parked or trying to accelerate/drive down the road? If it's the latter, it could well be the transmission slipping. Does it feel like the car is randomly shifting gears, or going out of and coming back into gear? On some cars, that would throw a code for transmission slippage, but it likely has to be pretty severe before that happens. I'd say get thee to a mechanic.
 
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Some stored trouble codes will not give a MIL(malfunction indicator lamp) aka engine light. Is this when it is trying to shift? Or when trying to move from a stop?

Does it when shifting, from stop to start it's ok, while I'm driving it starts the hesitation. I was just wondering if anything from Autozone would tell me, without having to take it somewhere to get it diagnosed for 70-80 dollars, when it could just be a dirty fuel injector or something.
 
Does it when shifting, from stop to start it's ok, while I'm driving it starts the hesitation. I was just wondering if anything from Autozone would tell me, without having to take it somewhere to get it diagnosed for 70-80 dollars, when it could just be a dirty fuel injector or something.

It definitely sounds like a transmission issue. Have you checked the fluid?
What is the make and model of the car?
 
I wouldn't think that would be the root cause of your problem. Leaving the filler cap off with the engine running would cause oil to leave the engine. There's plenty of moving parts under there that throw oil around inside there. It's like a blender: if you remove the lid while it's on, your milkshake is going to exit the blender real quick like.

It could be a potential idle air control valve or PCV valve issue (if your car has one). Failures of those should throw codes that would put the check engine light on, assuming that your check engine light works.

Well maybe I only partially explained it lol..I had the engine oil cap for 3 weeks and oil came out, prior to that the engine oil light was coming on. I poured Eng Oil in it and accidentally left the cap off for 3-4 weeks and oil came out. It started acting weird so I went and got an oil change, and they told me my oil was low.
 
I'm afraid it definitely sounds like a transmission issue. Though like I mentioned, the AZ check is free, so you can always start there. But I'd try to get to a mechanic soon. Sorry.
 
How long has it done this, and is it fairly constant, or just here and there?
For example if you got in it and drove say 5 miles, how often would you guess it would happen?
A transmission fluid and filter change could buy you some time, but it is usually a downhill slide once this begins. It's usually around $100(here in TN) for the flush, where a rebuild can be $1000 +. So I guess I'm saying it could be worth a try depending on the extent of the damage so far.
 
1998 was only a couple years after most manufacturers started doing the more advanced electronic engine controls (when the OBDII (on-board diagnostics) standard was published in ~1996) As such most cars were on their first generations of those electronic controls. At that time, most did not have transmission monitoring - it was mostly watching intake and exhaust sensors for emission controls and proper fuel/air mixture. So, no surprise that there is no dash light. It's unlikely that there is any code being thrown at all. Generally speaking a light will come on steady if there is a minor code, and flash if there is something more serious. This assumes the bulb isn't burned out :001_smile .

As said, what you have is almost certainly a transmission issue. You need to get it to a transmission shop. It won't hurt to have the OBD codes read, but it's unlikely to show anything.
 
1998 was only a couple years after most manufacturers started doing the more advanced electronic engine controls (when the OBDII (on-board diagnostics) standard was published in ~1996) As such most cars were on their first generations of those electronic controls. At that time, most did not have transmission monitoring - it was mostly watching intake and exhaust sensors for emission controls and proper fuel/air mixture. So, no surprise that there is no dash light. It's unlikely that there is any code being thrown at all. Generally speaking a light will come on steady if there is a minor code, and flash if there is something more serious. This assumes the bulb isn't burned out :001_smile .

As said, what you have is almost certainly a transmission issue. You need to get it to a transmission shop. It won't hurt to have the OBD codes read, but it's unlikely to show anything.

+1
 
As [MENTION=106068]MichaelRB88[/MENTION] stated it is a transmission problem. If the leak is slow enough and there is not much damage I have had good luck with Lucas transmission fix. It would be a good idea to find out where it is leaking and change the filter too. It might be the leaking from same gasket that would be changed for a new filter. Oil and transmission fluid are the 2 fluids you really need to keep up on if you want to keep it hopping along. Good luck.
 
I was going to guess a 6th Gen Grand Prix. Had a similar issue with my '02 GP. I guess Fords of the same era were similar.
 
Fords had transmission trouble in the majority of their automatics. Probably still do.

It doesn't help that transmission maintenance goes neglected most of the time. With proper fluid changes every 30,000 miles or so, most of these issues can be avoided.
 
Yes I have a tranny leak, but I put tranny fluid in every week. It's a 98 Taurus

I think step 1 is getting the transmission leak found and fixed. If it's significant enough that you're putting new fluid in every week, then you're doing the transmission no favor by running it half-empty most of the time.

Replacing gaskets in and around the transmission scares the heck out of me, and I've done my share of DIY repairs. I think that you should look for a good transmission mechanic to diagnose the leak, give your transmission a good once-over, and give you an estimate on what it would cost to fix it. Unfortunately, I have a feeling that it will be cheaper to upgrade to a newer Taurus than fix the tranny on yours.
 
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