No start but have spark and fuel

D

Derbyguy919

I just did the timing belt on my newest P5,it is in time,it’s getting spark and fuel but it won’t fire. Noticed antifreeze leaking from the exhaust as well🤢 couldnt see any leaks on the outside but haven’t torn back into yet. What could be the issue though? Warped or cracked head along with the gasket?..I’m stumped for now,any advice would be greatly appreciated
 
pcb said:
A compression test will let you know.

A leakdown test will tell you more.
Click to expand...
I was gonna try a compression test in the morning. Forgive me for asking, but what is a leak down test exactly? Vacuum leaks? If so we checked that earlier and everything was good, has power to everything it just won’t turn on at all. It also took about 6 key bumps to break the crank bolt loose if that means anything? Figured it was the not fully charged battery but now I’m leaning towards low compression somewhere.
 
I missed your earlier question.
A leak down test is similar to a compression test but you feed air pressure in through the spark plug hole and see if any leaks out.
It's a more accurate test for leakage compared to a compression test.

You may have a warped head but you may be able to get the new head gasket to seal it up enough to not leak if the warp is very minimal?

It would suck to install a new head gasket and have it still leak, then have to do it all over again with a new or machined cylinder head.
 
You should really replace the cylinder head or have it inspected/machined before reinstalling it.

You "should" replace the head gasket and bolts if it doesn't seal and end up having to do it over.

I forget your circumstances but I think you've got two cars and the engine on the one that's burning oil probably has a good cylinder head.
 
pcb said:
I missed your earlier question.
A leak down test is similar to a compression test but you feed air pressure in through the spark plug hole and see if any leaks out.
It's a more accurate test for leakage compared to a compression test.

You may have a warped head but you may be able to get the new head gasket to seal it up enough to not leak if the warp is very minimal?

It would suck to install a new head gasket and have it still leak, then have to do it all over again with a new or machined cylinder head.
Click to expand...
I know exactly what you mean,I had a Honda Accord a few years back with a warped head and didn’t know until the 3rd head gasket change in a year lol. I used a trick I learned from one of my buddies years ago to check for warpage and it’s always worked fine for me. Put a straight edge across the head in various spots,shine light behind it. If you see light it’s warped,if not you’re golden.
im just really thankful that this page has about 5000 threads to use as reference. This is the best forum ever lol.
 
  • Like
Reactions: pcb
pcb said:
You should really replace the cylinder head or have it inspected/machined before reinstalling it.

You "should" replace the head gasket and bolts if it doesn't seal and end up having to do it over.

I forget your circumstances but I think you've got two cars and the engine on the one that's burning oil probably has a good cylinder head.
Click to expand...
If the head actually is warped,we’re just gonna put the good engine in it. Found a mountain of receipts under the seat for new timing belt,head gasket,oil seals and whatnot all done by a local shop. The “oil” leak turned out to be power steering puking out of a corroded line lol just like the other guy that had the same problem
 
Derbyguy919 said:
... I used a trick I learned from one of my buddies years ago to check for warpage and it’s always worked fine for me. Put a straight edge across the head in various spots,shine light behind it. If you see light it’s warped,if not you’re golden.
Click to expand...
Okay, that's cool! That should be accurate enough.
 
Everything is back together how it should be(we were a tooth or two off the first time) tried firing it earlier and all it does it crank still..could the crank sensor be out?? That’s all I can think of at this point
 
If you still have spark and fuel, then your crank sensor is probably working properly.

You can inspect it if you don't have spark.





 
It actually turned out to be the crank censor...well,part of the problem. Took the old one off and noticed the ground wire had been pinched off at some point before we started tearing it down. Now it tries to fire up with a spray of starting fluid but I think the gas in it is so bad that it’s drowning out the spark lol. Tried to siphon a little out of the tank(lol yeah right) to test it and got a few drips in a fresh cut. It didn’t even hurt so I’m gonna guess the gas is trashed at this point. Gonna remove the fill tube and siphon the tank from there because the screws holding the sending unit in look sketchy,fill her with some fresh gas with a splash of octane booster and fuel treatment and hope she finally runs. I seriously hope this fixes it..if the fuel pump is bad,I’m welding my fuel cell in the back seat and running it like a derby car lmao
 
  • Like
Reactions: pcb
Here's a link to the fuel filter replacement thread I wrote...

How To Change Your Fuel Filter (lots of pics)

Thanks to mtnbiker26 for starting his thread and everyone who contributed to it. http://www.mazdas247.com/forum/showthread.php?123718385-Has-Anyone-Had-Their-Fuel-Pump-Cover-Leak I finally got around to installing my fuel filter using the how-to. The first and easiest step is to lift up the...
www.mazdas247.com www.mazdas247.com
Keep in mind that they are not Philips head screws.
They are JIS.

A Phillips will strip the screw heads.
 
pcb said:
Here's a link to the fuel filter replacement thread I wrote...


How To Change Your Fuel Filter (lots of pics)

Thanks to mtnbiker26 for starting his thread and everyone who contributed to it. http://www.mazdas247.com/forum/showthread.php?123718385-Has-Anyone-Had-Their-Fuel-Pump-Cover-Leak I finally got around to installing my fuel filter using the how-to. The first and easiest step is to lift up the...
www.mazdas247.com www.mazdas247.com



Keep in mind that they are not Philips head screws.
They are JIS.

A Phillips will strip the screw heads.
Click to expand...
Awesome thanks man! That’s gonna be last resort I guess,I really don’t wanna take the fuel pump cover off lol I know I’ll end up breaking something. I already broke a plug for one of the injectors(luckily I could glue it back together) dry rotted plastic sucks
 
  • Like
Reactions: pcb
Drained the old gas,put in some fresh and it fired maybe twice now nothing again..starting to get pissed off at this point. Fuel filter looked good,my only guess is it’s still pushing old gas out of the lines. If this doesn’t work I’m done messing with it
 
Don't give up now, you're too close.

Have a few beers, smoke a J (if that'legal in your state), and sleep on it.
 
pcb said:
Don't give up now, you're too close.

Have a few beers, smoke a J (if that'legal in your state), and sleep on it.
Click to expand...
That’s what I’m doing now is taking a break for a little bit. I definitely need herbal inspiration trying to get this old girl going again lol I never would’ve imagined it would be this big of a headache. I’m too spoiled to easy Honda and Chevy engines I guessed
 
I remember spending at least half a day putting my T-belt on and off 8-12 times.
It looked perfect until I spun the crankshaft around.
I was always off by one tooth.

I wanted to take my sledgehammer to it. Lol
 
pcb said:
I remember spending at least half a day putting my T-belt on and off 8-12 times.
It looked perfect until I spun the crankshaft around.
I was always off by one tooth.

I wanted to take my sledgehammer to it. Lol
Click to expand...
That was me after redoing the head gasket lol I never wanna have to clamp two wrenches together again. I clamped my finger more often than the wrenches lol wish Mazda would’ve made the cam gears like Honda so you could just clamp them together. If my dad wouldn’t have been helping me with the P5 I would probably still be trying to get it in time. I was pretty close to sending a wrench through the windshield a few times. The car is lucky it’s in decent shape,if it would’ve been the beater P5 I would have just flattened it with the backhoe by now lol
 
Please log in or register to reply here.

Similar threads

Chanman117
Crank no start msp swap...Help!
Replies
11
Views
2K
sleeprp5
S
Y
Seeking guidance with two issues for Protege5
Replies
10
Views
2K
YELL0WP5
Y
T
Rough Idle, Loss of Power and No CEL (2003 Protege5) - Solved!
Replies
15
Views
6K
BenjiHoggi
BenjiHoggi

Latest posts

Back