TabMan

So I changed the following on my vehicle. A lot this due to the fact the car was not maintained very well prior to me and I bought it earlier this year.

Timing Belt, Water Pump, Pulleys, Idle bearing, Belt Tensioner, Spark Plugs, Valve Cover Gaskets, Cam Seals, Crank seal, Knock Sensors, Knock Sensor Wire Harness, Coolant Hoses, Intake Gaskets, Throttle Body Gasket, Air Filter, PCV Valve, Fuel Injectors Coolant, Oil.

When I rehooked the vacuum hoses I made sure to follow the diagram on the hood I had handy. I have gone through and triple checked and can't seem to find anything wrong there.

The car starts normal when hot, when cold is have a slight hesitation that doesn't seem apparent then accelerating. Though when I change to reverse sometimes it delays to change gear and the truck vibrates/rocks. Other times (even when cold) it will go right into reverse.

On a test drive I find a delayed slightly hard shift into one, then a hard shift into 3rd and a shake / jerk into 4th where the shift is delayed and the truck jerks/rocks. This continues whether engine is cold or warm.

What I feel to be honest is a vacuum or a gasket leak but I'm not sure. I changed some of the tranny fluid by simply draining and fill. Fluid was greyish pink, no shaving on the drain pan bolt.

Any ideas I will welcome with open arms. I do have a vacuum pressure gauge on the way. I also plan to use a multimeter on the Throttle Position sensor to check that. But I'm really scratching my head here.

Ran scans today, nothing comes up for DTC's.

Also to note, when I press the accelerator gently when cold, there will be a delay/hesitation and sudden boost of the engine. It's less apparent when the engine is hot. Sometimes with the delay/hesitation there will be a slight loud pop like bubble gum.

Could it be I messed up the one of the 2 intake gaskets or don't have a proper sealed.

Here is a video I took in attempt to capture it.

Kolton5543

Sounds like a typical sensor problem. Based on the way it does odd things to both the engine and transmission it sounds like a TPS going bad. A TPS is nothing more than a variable resistor. One going bad is very sensitive to temperature differences. The only real way for it to set a code is if it's a circuit code. Meaning it's open and there is no voltage output or its shorted and only outputs 5v reference or ground. If it shows an incorrect value it won't set a code because the ecu doesn't know it's incorrect as it the only sensor to tell it where the throttle is.

I'd recommend giving it a test. There should be 3 wires to it. Connect a multimeter and check its readings. One is a ground. One is a reference voltage. Should be about 5 volts key on. The other is sensor output. With the throttle closed it should read about .5 volts and about 4.5 volts open. Slowly open it and make sure the voltage rises steadily and smoothly. There should be no dead spots or spikes or drops in the voltage. If there is replace it. Also check it at different engine temperatures. It may test fine hot but fail cold.

TabMan

Buddy I'm going to check this today and report back. Man I hope that's the issue, I'm at a loss.

TabMan

Ok I checked the voltage of the TPS reference wire and got 5.15v, but when I went to locate the ground which should have been the the 3rd wire form the reference, I was not getting an signals of a ground, nor from the middle wire. So it is looking like I might have a bad ground?

Kolton5543

Its very possible you have a bad ground connection some where then. The TPS, MAF, VPS and CTS all use the same ground. Check to make sure they all have a ground too and check the back of the motor where they source it from. Likely on a head

TabMan

So I checked the MAF and got the sames results. Is there a diagram that shows where the ground for this is. My suspicions are they are located toward the rear passenger side towards the bottom.

Also I did this test, I I put 2 pins in the back of the plug, one into the reference and other into the ground, got nothing when I tested for volts but then I took an alligator clip and ran it to a ground.

I then did my ground test again and obviously got my multimeter to beep this time. Now when I do a volt test and touch the ground and the reference I still get about 5.13 volts.

Shouldn't I be seeing about .5 volts there? When I moved the throttle up and down, it didn't care.

Kolton5543

No, 5 volts is what you want to see on the reference wire. That wire comes from the ECU and supplies power to the sensor. .5 volts is what you want from the signal wire coming out of the sensor.

Kolton5543

Kolton5543

From what I can tell from the diagram white should be ground, blue/red should be 5v reference, and black/white should be signal.

TabMan

Anything to give me an idea or any tips in finding the bad ground? Or pointing to the right area to look for it?

TabMan

You're right, I'll double check tomorrow on that.

Kolton5543

Its listed in the diagram. It says the ground location for those sensors are on the rear of the engine. Its likely on the head.