Help starting a P5 that's been sitting for years?

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2003 Mazda Protege5
Hey y'all, it's been years since I've posted, hence the title...my P5 has been sitting for about 3 years or so, and I'm working towards getting it back on the road. There were no engine issues before the car sat, so it should be fairly easy to get my P5 going again, I just want to make sure I'm going about this the correct way. I was obviously planning to change the oil and get a new battery (it's dead dead), and then I have some questions about what else should be done before trying to start?

I was thinking I should drain the radiator and fill it with distilled water at first (before mixed coolant), just to make sure everything is good before possibly wasting the coolant?

I'm pretty certain the gas is trash at this point, correct? So, that should get siphoned out beforehand (and refilled)? Is it easy enough to siphon through the tank filler neck? Or do I need to siphon by removing the fuel pump first, and going in through there?

I'm thinking the transmission fluid should be changed as well?
What about spark plugs?
Should I hand crank the engine first to make sure it's not stuck before trying to start it?

Though all of this may seem super obvious, I just want to make sure I'm on the right track and I don't mess anything up on my P5. I don't mind doing the work, as I've done these maintenance tasks on my P5 before, just wondering if these should all be done BEFORE a start up after sitting for so long...just looking forward to getting my P5 back as my daily driver! Thank y'all in advance!
 
If it were me, I'd only worry about the gas.
If it has about 1/3 of a tank of gas or less, I'd throw in some fuel stabilizer/conditioner then fill the tank with fresh gas and see if it starts.

It would suck to do all those things you mentioned, and then not be able to start it.

I had a Mazda GLC that sat for 8 months that just fired right up.
 
I think is better to wash the tank before refilling it. There is probably rust inside it.

Check the wheels, they could be damage for the amount of time without moving
 
Thanks for the replies! So, the car sat for a little over a year initially, and it fired right up with a fresh battery when I moved it over to the new house. Now that was about 2 years ago, so it’s been sitting for 2 additional years and I’m just worried about that gas. Correct me if I’m wrong, but will the fuel stabilizer help anything? It’s my impression you put this stuff in with fresh gas to make it last? I agree I should clean out and wash the tank - is that straightforward enough? I searched the forum and keep stumbling on gas tank replacement threads and they mention cutting exhaust? Just looking for the best (and easiest) solution possible.

Edit*** - concerning cleaning out the tank, the options I’m mulling over are, siphoning from the filler neck (is this possible?), or removing the fuel pump/unit and going in through there...what do y’all think? Or if it’s under 1/3 full, should I add berrymans or sea foam plus new gas? I may be overthinking it, but the old gas worries me. I’m gunna get underneath the car sometime this weekend and check the tank for rust as well.
 
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You could disconnect a fuel line under the hood, connect the jumper wire for the fuel pump in the OBDII port, and pump your old fuel out.

Or you could replace your fuel filter and gain access to your gas tank.




I replaced my gas tank because it rusted out.
There was no rust inside the tank.

The tank either leaks fuel, which stinks, or loses its seal and you get all kinds of EVAP codes.

Don't fix what ain't broke or you'll end up having to fix what you broke trying to fix something that wasn't broken.






Replacing the fuel filter is a good idea anyway, and it gives you access to your fuel tank.


It's on sale at Rockauto...


 
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@pcb - as always, thanks for your insight and detailed response!

You could disconnect a fuel line under the hood, connect the jumper wire for the fuel pump in the OBDII port, and pump your old fuel out.

I thought about getting the fuel out this way, but I guess I was a little apprehensive about sucking up crud through the lines, however much that matters..?

I was wondering if I might be able to siphon directly out of the tank, going in where the joint hose (3) meets the tank?

Screen Shot 2021-03-06 at 2.37.57 PM.png


What do you think? Otherwise, I'll go in through the back seat/gas tank access panel, or the DLC/fuel line route (if it won't harm the lines).

I'm about to change the oil on my truck, so I'll finally get under the P5 after that and see about rust. Thanks again!
 
There is a filter sock/screen on the input of the fuel pump that should catch any big chunks of crap and the fuel filter/fuel pump housing will catch anything else.
But you don't want to plug up the filter.
The fine particles of crap that get caught in the fuel filter tend to be stirred in the gas and don't necessarily sink to the bottom.

You don't want to run the fuel pump dry.
That can wreck your fuel pump.


You could disconnect part number 3 to gain access, and you may be able to stuff a small tube right down the filler neck but I'm not sure about that.

Some cars have screens in the filler neck to prevent your fuel from being stolen.


As far as rust goes, I would just wait until the tank springs a fuel leak or a vapor leak before replacing it.

It's kind of a dirty chore to replace but I had rusty bolts that snapped.
I had to drill new bolt holes to bolt the tank back up.
 
This is a picture of the fuel pump housing and screen/sock.





Replacing the fuel filter is a good idea because it could be close to plugged up and that can burn out your fuel pump.

It would be a good excuse for the effort and you can empty the tank that way and see the crap in the tank.


 
I did something similar a few months ago to my sisters talon. It had sat for 4 years with a broken timing belt. After 4 years she decided it was time to get it running again. Changing the coolant was done here out of necessity not because it sat. I put a new battery in it and the fuel gauge said 1/2. So i bought some iso-heet and put it in the gas tank. Its supposed to help with moisture/water in the fuel. The car started and ran. But it was rough. I thought it was fuel related so we siphoned the tank from the plate under the backseat. We used a hand transfer pump from harbor freight. Also was a good time to replace the fuel pump and filter. Turns out it was 1 tooth off on exhaust so all that work wasnt necessary. Good to have all new parts after sitting that long but like I said- it fired up and ran with 4 year old gas and plugs. Iso-heet might have helped idk but like you i thought the stabilizer was a pre additive. I hope this helps. I also agree with pcb -get it fired up then replace parts so at least you know it will start.
 
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Welp, 7 months later, and I finally got my long-time sitting P5 to start! All I did was inspect the plugs (they were clean), change the oil and put in a fresh battery. It cranked right up! I know I took the less ideal route, cranking it with the old gas in there, but hey, it started.

That being said, there's still 1/2 tank of old gas in my P5...should I run it all through and burn it out? Or maybe try pushing it out using the diagnostic thing, basically getting the pump to run the fuel out, you pop the line and catch the old fuel in a container method...I know the old gas is no good, but I'm just asking y'alls advice again. I let the car run for about 10 minutes and get up to temp, everything was fine, but it did start running a little rough in between coming up to temp.

Just wanting to get through this part of reviving my P5, then I can move my focus to overhauling the entire brake system, changing ALL fluids, and then hopefully have my daily driver back...

As always, thank you in advance for any advice/input!
 
If it were me, I'd just top it up with fresh gas and some iso-heat or something, and not worry about it.

Or if you are planning on replacing your fuel filter (which is a good idea), you could siphon out the old gas through the opening while the fuel cover is off.

I would think that if your car was running, it will keep running.

Something added to the gas to absorb moisture would be a good idea, in case there was any condensation inside the tank. (like gasoline antifreeze Methanol or isopropyl alcohol.)
 
... I let the car run for about 10 minutes and get up to temp, everything was fine, but it did start running a little rough in between coming up to temp.

That may have been your IAC relearning how to idle the car.

Whenever the battery is disconnected (or is completely dead,) the IAC needs to relearn how to idle the car.

Once the engine reaches a certain temperature, the ECU hands over the idle control to the IAC, where it may struggle to idle the car.
You may have a really rough idle, or very low idle, or it may even stall, depending on your particular car.
 
@pcb coming through clutch, once again! Thank you for your quick replies.

For now, I'm not smelling any gas or noticing any symptoms that would warrant the fuel filter swap, so I'll go with the path of least resistance and top off the tank with fresh gas and maybe some iso-heat or something of the like, I'll do a little research.

All of the symptoms you described of the IAC relearning how to idle the car sound exactly like what I was experiencing, rough here and there, wanted to die but didn't, idled real high at first, then real low at one point (where it was getting rough), but evened out for the last 3-5 minutes of that 10-15 minute warm up.

I'm gunna focus on the brake system next, get all that back working correctly, get it driving a bit and see what comes next. I'm anticipating a leak popping up, idk why, just because all of the gaskets/seals having sat for so long...I plan on changing the gear oil (I have a manual) as well, once I get the brakes back to working 100% first. One step at a time.

Thank you again for your insight!
 
For now, I'm not smelling any gas or noticing any symptoms that would warrant the fuel filter swap,...
Don't wait for symptoms, or you'll probably burn out your fuel pump and maybe be stranded.

Changing the fuel filter should be part of regular maintenance.

so I'll go with the path of least resistance and top off the tank with fresh gas and maybe some iso-heat or something of the like, I'll do a little research.
Yes.

The fuel filter does not necessarily need immediate attention, but it should be on your to-do list...

All of the symptoms you described of the IAC relearning how to idle the car sound exactly like what I was experiencing, rough here and there, wanted to die but didn't, idled real high at first, then real low at one point (where it was getting rough), but evened out for the last 3-5 minutes of that 10-15 minute warm up.
P5 rough idle... Help!
 
...I plan on changing the gear oil (I have a manual) as well, once I get the brakes back to working 100% first. One step at a time.


You might want to consider using Synchromesh oil for your transmission if you live in a cold climate.

In the winter, my car would grind every gear for about 15-20 minutes until my transmission warmed up.
Synchromesh oil solved the problem.

It's kind of expensive, but so is the Redline stuff, and it lasts for years.

I've had mine in for almost 10 years now.
 
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