A couple of 1st Gen questions

[tundrayetti]

I just bought my first T4R yesterday. It's a '88 2.4L 4WD

First, I have attached a photo of a sensor that sits on top of the valve cover. One of the vacuum line attachments is broken off and I would like to replace it. However, I don't know what the name of the sensor is. Can you tell me the name of it?

Second, I have an intermittent acceleration issue. Intermittently, she runs pretty rough when accelerating. Gas pedal must be depressed approximately 90% to get her to accelerate. Anything less than 90% throttle, and she deaccelrates and runs just plain rough (almost like a fuel problem). A couple of miles down the road and she frees up and runs like a dream (which tells me it's not a fuel problem). It's really hit or miss when she acts up, sometimes not at all, other times for 20 minutes or so.......any thoughts?

Thanks

 

[SV_Dude]

The sensor in your picture is the A/C idle up VSV (vacuum switching valve). Basically, when you turn your ac on the VSV will make your truck idle 100 rpm higher at an idle.

The second issue, I would check out your throttle position sensor. That is the sensor that is on the driver side of your throttle body. It tells your ECU how much you're pushing down on the gas pedal and the ECU accounts for how much gas to give the motor.

Look in the sticky at the top of the forum. There is a link to the factory service manual. In the FSM it will tell you how to check and adjust your TPS.

 

[tundrayetti]

Thanks for the help SV.

I spent this weekend replacing the clutch assembly and diagnosing my acceleration issue. Here's what I found regarding the acceleration issue...

Throttle Position Sensor - I removed the throttle body and ran a diagnostic check on the TPS. Everything checked out, so I re-installed the same.

I then decided to check the Air Flow Meter. I was getting higher than normal readings on my meter (around 2000 ohms) initially. So I opened it up and found that there was a slight (very slight) groove on the potentiomenter underneath the A-shaped contact. I carefully lifted the contact and inserted a small strip of 600 grit sandpaper. I pulled the sandpaper back and forth 8-10 times and to my surprise, my readings dropped into the "normal" range. I sealed the meter back up and replaced it.

At this point, I was preparing to buy myself a new Air Flow Meter. However, she's been running great for two days now. I'm hoping it stays this way.

Anyone have any similar problems with the Air Flow Meter?