Rough Idle 1993 Toyota Tercel, what's wrong?

Question

So I changed my water pump, and in the process i took off the fuel pressure regulator, because i thought it was in my way. When putting EVERYTHING back i could not find the Bolt (union bolt-like a bleeder screw) that goes on top of the regulator. So I needed the car and got a bolt that fits the size, and I drilled holes to the bolt, for temporary use, but i believe not enough fuel was being delivered. I drive the car and its idling rough, and is using a lot of gas. I driven the car for about 200 miles, and I finally went to get the right bolt at the dealership. I put this bolt in its place, and drive the car around, and its the same. What would cause the car to idle back and use up a lot of gas? Please help.

-Does the ECU have to memorize the fuel/air induction?
-Might I have a vacuum hose that just went bad?
-Please help

Answer 1

While the little car is idling, with the hood open, can you hear a pronounced "hiss"? If you are not sure, with the engine idling, use a can of carb cleaner and spray around the intake area, particularly in the area you were working. If there is a change in the idle and it smooths out, locate the leak and repair it.
Be certain that you replaced everything else correctly. I know, you probably have checked, but check again. You admittedly lost one of the pieces, so, if necessary, go back and re-check EVERY place you put your hands.
If this doesn't turn something up, there could be a coincidence.
Go here------>

http://autorepair.about.com/library/ts/obd-i/bl-dtcs-48a.htm

...and scroll down below the descriptions, and follow the procedure for retrieving codes. If there are any, write them down, and refer to the description(s) for the areas of needed attention.
If there is a code delivered for a particular system, refer to a repair manual and follow the proper DIAGNOSTIC routine first, BEFORE repairing or replacing any component(s). One system (eg. fuel) can affect mixture, and can cause a code for a MAP or O2 sensor etc.
Check that you replaced all of the plug wires in the correct order and on the correct plug.
Basically, check the basics. It was running before you started. Look to see what YOU did that changed it. It doesn't take much, and when you find it, you will probably feel really dumb. I know I do when I do those sorts of things.

Good Luck and Merry Christmas

Answer 2

not knowing the history of the vehicle or engine family(model) if this vehicle has a timing belt make sure it is ok and all the marks line up if the timing is even out one tooth it will cause a problem.if your engine was running good prior to the water pump than you may have disturbed a hose a fitting(vacuum connection ) or wire may be off. make sure there is not excessive pressure in your cooling system,possible head gasket this is dependant on how low and how long you drove the vehicle with a bad water pump.

Answer 3

i own a repair shop,and it probably wouldn't be a bad idea to go back over everything,and check and see if anything is off of it,,or loose on it,,it sounds like it might have a vacuum line off of it some where that will cause it to drink gas real bad ,but i think if you check it all out,,you,ll find it,,good luck with it,i hope this help,s.

Answer 4

I honestly have a 1991 tercel and it idled relatively undesirable once I first have been given it, i only took it to a private shop the place they only do toyotas and it is plenty extra effective now, it nevertheless shakes a sprint like at purple lighting fixtures fixtures or on the throughway, yet definately no longer almost as undesirable.