Strange hesitation Options

[6G96GT]

EDIT - Today, this morning I tried to start it. She fired right up but then immediately died. Tried again and heard a couple backfires and popping and died again. I tried to hold the gas down a little to see if I could hold it with gas... couldn't start, seemed like it had no fuel even though it's half full. Any ideas?



Hey guys, my car's been running real nice for the past couple years and is cam'd and tuned since Oct. 2012 - put about 12k miles on it since the cam install and tune. Never had an issue.

Anyway, today getting on the highway car started acting funny and started hesitating. Then it turned into a real rough hesitation and forced me to slow down from 65 mph to about 35 mph. Finally came to a stop and she died. Turned right back on but very poppy. I was able to get it back up to 60 mph to make it home but was hesitating quite a bit...almost sounded like a quite machine gun at times.

Also, once off the highway when nearing a stop, she got really poppy and wanted to quit. When at a stop light, the idle would fluctuate from 600 to about 1,000 rpm.

Things I noticed:

- hesitates a lot under local and highway speeds
- smells like fuel
- usual bass exhaust rumble got less powerful sounding

Could it be fuel filter? Fuel pump? What gives!

Temperature was normal and oil pressure normal.

This post has been edited by 6G96GT: Feb 2, 2014 - 10:41 AM

[Kev6GCTH]

Check spark plugs and ignition system (tension cord and distributor)

[blockustomz]

Did you ever replace the fuel filter or the pump recently?
Hows the oil look & radiator fuild?
Maybe bad gas..?

This post has been edited by blockustomz: Feb 4, 2014 - 12:32 AM

[6G96GT]

Oil is perfect - I use mobile 1 full synthetic. Coolant looks good. All gauges read fine. Haven't changed the fuel filter or pump ever but I just bought a new filter from Toyota along with a new ignition coil. My buddy said the plugs and wires look great as does the cap and rotor. I did get gas at another location but it was a Hess. Isn't that good gas?

[blockustomz]

Oil is perfect - I use mobile 1 full synthetic. Coolant looks good. All gauges read fine. Haven't changed the fuel filter or pump ever but I just bought a new filter from Toyota along with a new ignition coil. My buddy said the plugs and wires look great as does the cap and rotor. I did get gas at another location but it was a Hess. Isn't that good gas?

It's good gas but in florida we recently had a problem with water in our gas.. Wasn't sure if you pumped and then this happened..
Filter is a good start could be clogged but it sounds like the pump.. let us know.. If you can check the pressure from the pump after the filter change.

[Tigawoods]

sounds like the exact same problem I had when my distributor went. take the cap off and see if it looks like the coil pack has gone

[6G96GT]

I'll check on the FP too. I did buy a new coil in case that's also a culprit.

[VavAlephVav]

and once you get it figured out please be sure and post, I like to find out ahead of time in case mine starts doing the same thing
ty

[6G96GT]

Hey guys, this weather we're getting in NH really sucks. I have not been able to do the work yet but I plan on tackling it this weekend. One thing about the fuel pump and trouble shooting...is there any tips for testing to see if it's good without having to access it just yet?

[6G96GT]

Just posted a new topic question for fuel related issues to this thread. Anyway, here's a question from that post...

When checking the ignition coil, I pulled off one of the spark plug wires and set it next to the metal frame in the engine bay...like 1" away. I then attempted to start the engine. It started but no arching came from the plug wire. Did I do something wrong here?

[VavAlephVav]

not sure about that test, but if you can come up with a multi-meter you can measure the coil resistance it should be about .4-.5 ohms on the primary and 10.2k-13.8k ohms on the secondary.
but you have to take the coil out to do that.
the test like you're doing says it should be 1/2" away from the frame(idk how big of a difference that is)

also if you take the cap off with the wires connected and measure with ohm meter from the inside of the cap contact to the end of the plugwire it should be less than
25k ohms. which shouldn't be a problem if you've replaced the cap and rotor in the last several years ( you said you had a lot of work done to it, but did they neglect the cap/rotor and wires?)
for the most part even if you don't have an ohm meter (you can get a cheap one for <$20) but if you take the cap off and look at it you could see if there is a lot of carbon built up on the contact surfaces
of the cap points and rotor thingy

This post has been edited by VavAlephVav: Feb 8, 2014 - 5:24 PM

[6G96GT]

Thanks for your reply. I do have a meter. I'll check out those numbers you mentioned. The cap, rotor, and wires were done at the same time so they aren't too old. My car started up today and ran for a few seconds...so weird.

[VavAlephVav]

sometimes if you have plugs/wires/coil ignition problems they can be effected by the humidity in the air and kinda work one min but not the next
or get worse as the motor warms up


This post has been edited by VavAlephVav: Feb 8, 2014 - 9:37 PM

[6G96GT]

Okay, so all done and said. It was the map sensor. $65 to solve the problem. Gotta love it.