The car was driving down the road, I hit a bump in the road and it started acting like there was no gas and backfiring.

I put a new fuel pump, reloaded my map, reloaded firmware and map, and new plugs. The car starts up and runs but the tach is off and the car boggs. I pull over recheck my fuel injector wiring. The car starts up and runs beautiful.
(my car needs shocks bad, the hole highway is a continual bump here)
So I go to exit off, I have hit bumps the hole way,and hit another bump and the car just dies.

I pulled the plug and spark hits some but not always.

So I swapped a ignitor, nothing, and a guy gave me a cas he had off a spare motor of his. Still no spark.

#1. Do you thin the ignition went out. Has anyone had this problem, while driving?
I checked all over the car for wiring. It seems to be good.

#2. I guess I'm going to have to swap in a oem ecu and see if that starts it.

#3. Any suggestions?

 

I installed the cas, still no spark.

 

i'd start the car and just give all the major harnesses a good tug while it is still running, (a la ford and their "wiggle test") it sounds like something is loose.

 

I can't get it to start. I also haven't cut into the factory wiring.
There is a spot in the back by the battery, it has been spliced into but looks like clean cut off. Mabe something for a sound system. And there is a factory 5 or 6 wire plug with nothing in it coming out of of the factory harness by the battery. What is that?

 

That definatly sounds like a bad conection, seen this happen alot in my shop.

 

What wires specifically do this commonly?

I want to race on Sunday! I finally get MAN time again. And I don't want to be hotroding the Tarus.LOL!
My girl doesn't want me hurting her miata.

She says I can work on my own car, leave hers alone. Hahaha.... I reply, I was just trying to help.

 

Ignitor or coil pack. Swapping a broken igniter for a broken igniter won't help. Make sure the parts you are swapping are known good parts.

 

are ALL of the guages reading in megatune? could be a bad ground too

 

+1 Todd

 

Everything is reading well, the ignitor was taken off my brothers car. i put the old one on his to see if it worked. His car fired right up.

I was thinking if it was a coil pack that only one coil would of died and it would of started missing.
The car just straight up died. Like a kill switch. I've checked the grounds...........Except, is there is one on the tranny. and I just had the clutch put in. I hope that is it.

Unless the used cas that was given to me was bad as well.....He said he took it off his spare motor that was running spark fine. He just wore the motor out racing.

 

Is there any relays that could cause this?

 

Check all the grounds if they are in question. If one coil pack dies, then the engine bogs, map shoots up, MS dumps fuel, and then the half that was running floods and the engine dies. If this was the case putting it in flood clear mode (WOT) it would start after a few seconds on two cylinders. Bouncy tach say's this is the ignitor or coil pack. Or possibly a bad CAS. Verify the parts you are swapping are good. [echo/]

 

bouncing tach also signifies a dead or dying battery

 

Will it do this with a good altenator while drivng?
I had a motorcyle do that once now that I think about it.

But the battery will still turn the car over. So it isn't shot. But I will re-adjust the positive cable. I hate the factory cables. They don't tighten enough around the post. The ground has already been replaced.

I'm going to crimp that thing till it almost breaks.

The car had good power and bright lights when it died the last time.

Thanks for pointing that out.

 

yeah, it'll still happen with a good alternator but bad battery. but if the lights were bright and it seems to be turning the engine strongly, its probably good, wouldn't hurt to hook a trickle charger up to it over night though.

my next guess would still be grounds. check the small ones bolted to the back of the intake manifold, and below the brake master cylinder booster, along with larger grounds back by the battery and from the rear of the exhaust manifold (its actually on the block) to the chassis.

 

Make sure that there is not any corrosion coming from inside the rubber cover on the grounds. Sometimes its hard to see under there so if it looks like there is some peel the rubber back a little and check. Hidden corrosion in extreem cases can cause a bad ground.

 

The 2 most common things i see are a loose ground, or a wire with the insulation worn off rubbing on something when you turn or brake or hit a bump. I found this one time my car would completely die when i tuned left, I was my stock O2 wire grounding out, It caused me to spin on the track.

 

Hmmmm.... It is on like Donkey Kong! I'm goig to spend the day trying to get it together. Hopefully I can get it done by 2-4. I would like to hit the drag strip.

 

Just check all the connections first and make sure you are getting spark on all 4. My guess is dead coil pack...

 

I checked for fire on both coils. Sometimes when the key first turns on. It will pop in the exhaust. When it turns over it may spark twice, and nothing.

I checked the grounds, fuses, and connections. There is one plug not plugged up. I should have a picture of it shortly. I think it is for a sensor tempsensor.

My guess is the ignition switch.