Been having problems with my 93 again. Lets start with the basics, rebuilt super stock 3.0, regeared, auto tranny, 4" lift with 35's, 200k on the body.

I've this issue for about 3 years, and now it's a common occurrence and is starting to become dangerous. The trucks idle is very low, on either hot or cold days. Never a problem on hot days, just shakes the truck a bit when stopped. On cold days, the truck will idle so low that eventually it stalls out. Sometimes at start up the idle is low (200-300 RPM) when its really cold, but for the most part it has problems after the engine has warmed up and has been driven around and then stopped at a stop light. The idle gets so low, that the lights dim, the truck shakes, and the brakes are stiff as a board. At this point if I come to quick stop the truck will stall out.

Here's part 2 to the story. When it is exceptionally cold, the truck has problems getting fuel to the cylinders, and basically the more i push on the accelerator the slower it goes. For instance, when going up a hill I will push on the gas to change gears for more power, and the car will decelerate and lose power. I used heat which seams to work fairly well, but today driving home from work it happened again to the point where i couldn't go faster then 30 MPH. If i pop it in neutral i can sometimes rev it up and get the engine to turn faster then 2-3k RPMS, but then soon after it goes right back into the normal power loss/ low idle.

Here's a list of mechanical parts replaced,
Engine 30k miles ago
Radiator 30k miles ago
Power Steering Pump 25k miles ago
EGR 20k miles ago
Fuel filter 20k miles ago
Brake Booster 10K miles ago
MAF 10k miles ago

The same issue has happened for about 3 years, but only on cold days. Ideas, thoughts, suggestions? I love this truck but if it continues to drive this way I cant drive it anymore. Help save the yota

 

A few things first off:

• How long ago was the engine rebuild? (days, months, years? What was replaced/rebuild? Who did this work?)
• Have you tried to raise the idle from the idle screw when the car is warmed up?
• Do you have any vacuum or air leaks?
• Has your throttle body been cleaned? Air filter replaced? TPS sensor working?
• Have you checked compression? Spark plugs, distributor, cap & rotor all working?
• The cold start injector could also be bad as it gives the engine more fuel when its cold outside.

 

Start with the easy stuff.

You mention your headlights go dim... Head over to Auto Zone and have them check your battery and alternator. Then make sure your cables and grounds are clean and tight.

 

1. Replaced the entire engine, complete rebuild from Oregon Engine Rebuilders. Its about 4 years old now, it is the "super stock" which is supposedly slightly more powerful then stock. Used all toyota belts when putting the new engine in just to be safe.

2. Have not adjusted the idle, basically it will idle at 1000 RPM or like 200 RPM, no ryme or reason why it does one or the other. It could literaly idle at 1000 RPM then at the next stop be at 200 RPM.

3.Not sure about Vacum or air leaks, don't you need a smoke pro or something similar to do that?

4. I redid the intake and did the ISR mod last year, at that point I did clean the throttle body (it was pretty dirty) and replaced the filter. I checked the filter a few days ago and half of it's pretty dirty, nothing crazy but I will replace it this week just in case. Last time I checked the filter I did find a little bit (very very minimal) amount of water in the intake tube, the truck does sit outside all year long but still dont really know how water can get in there...Haven't checked the TPS sensor

5. Have not checked spark plugs, compression, etc. But like i mentioned before the engine does run fine when it's above 40 degrees, all of these problems only exist when its cold out.

6. Whats the best way to check the cold start injector?

This morning she wouldent start at all, still kind of seems like theres water getting into the engine whether through the intake or fuel line, hmmm??