Van

There are 2 sensors in the bracket, at the back of the engine, that go into the bellhousing.

One "reads" a set screw on the flywheel so the computer knows TDC. The other "reads" the teeth on the ring gear so the computer knows RPM.

The computer then uses *both* the TDC and RPM inputs to make it's calculations on when to fire the spark plugs and the injectors.

It's important to note, if the fuel pump is running, you *will* have fuel pressure in the fuel rail, but that doesn't necessarily mean the injectors are firing.

Kenn311

I see the 2 sensors located behind the engine near the firewall so I am guessing those are the sensors that need replacing. I usually go through rock auto for parts and I don't believe I saw an actual speed sensor just the FI reference. Sorry just an additional explanation to the previous statement UP above. Thanks.

Van

Spend 15 minutes to do 2 things.

First, undo the 4 bolts that hold the fuel rail onto the intake manifold (2) and the cam box (2), and carefully wiggle the thing up so the injectors pull out of the intake manifold. Use a block of wood or something so you can prop this up so you can watch it under the open hood and crank the engine over - does fuel squirt out?

Second, get a timing light and clip it onto one of the spark plug leads and your battery terminals. Again, place it so you can see the light under the hood and sit in the car. While cranking the engine, does the light flash?

16valver

I didn't see a definitive response to whether or not you are getting tach bounce. What you should do is go to start the car when you know its going to be a no start. Keep a very close eye on the tachometer needle and nothing else. If your speed reference sensors are good, you should see the tach needle steadily bounce off the limiting peg by about a millimeter or two. If there is no bouncing then you have bad sensors.

Legoland and Van are giving you very good advice. It is always smart to use the process of elimination in the cheapest way possible to rule out potential issues. Then start throwing money and random things.

Legoland951

Both are the same sensor. Replace one, try to start. If it does not work, replace the other one with the SAME new one you bought (I have never seen 2 go bad simultaneously), and try to start again.

Kenn311

It's intermittent so it started fine and ran fine this morning. I'll definitely do what you said tomorrow VAN with the rail and injectors and see what happens. As far as the tach when it doesn't start again I'll be sure to see if it bounces as well. I have the reference sensor so regardless I'll be able to put that in hopefully in the next day or so. Listen this is a great forum and thanks so much again to all you guys for all your feedback. I've only had this car for roughly 2 months so it's cool to have knowledgeable folks giving advice on it.

fmartinez1897

JUST finished having the same issue. Turned out to be speed and Reference sensors. They were the originals actually fell apart in the mechanic's hands after he pulled them out.