86 celica Gt Hesitaion when accelerating

[mkopsick]

Ok guys help me out! When the car is idling and i hit the gas, the motor is very slugish then revs good, also when driving the car and I pull off from a stop sign its very sluggish then hauls butt. I checked the (TPS)Throttle position switch and it checks good according to the manual. The car is giving me a code 11 which is the TPS, TPS circuit, Nuetral start Switch, A/C switch or the ECU. What do you think it is? Could it be the cold start injector? or even if the TPS checks good could it still be bad? Should I recheck the timing? Any Help would be greatly appreciated....I also have the schematics for all toyota celicas digitized if anybody needs them. Just email me at Michael.Kopsick@robins.af.mil if ya need a copy....Thanks for the info....Mike in Centerville, GA

[Brainchild]

Hi Mike, welcome to TechIMO

If it's sluggish on takeoff, likely it couild be the timing.Possibly a dirty injector/carb whichever applies.Hard to really guess without driving the car.Some of the local suppliers here do diagnostic checks free(Autozone, Oriellys) Might check the ones in your area, they can test it and tell you what it is without guessing.

BC

[J-Excel]

Welcome to TechIMO.

Up until you started with all the technical mumbo-jumbo I would have said it was a dirty fuel injector. Especially given the age of the car. Also, I've found that cars past their prime run better on higher octane gas. I think you'd have better luck finding the kind of help you need on an auto mechanic forum.

[bigblue77]

Even though the TPS checks out good according to the manual, it might still be bad. But I would start with some injector cleaner tho since it is much cheaper. When was the last time it was tuned up? The fuel filter may also be plugged up a bit if it hasen't been changed within the last two years.

Good Luck

Jer

[mkopsick]

I've replaced the fuel pump, fuel pump filter, fuel filter, new plugs, new relays (all of them)

[jnas]

I would say that since you got code 11 that it is the TPS. The TPS is basically just a potentiometer. There could be corrosion or varnishing on the first section of wires causing the first part not to work correctly. That part will cost anywhere from $70 to $100 so depending on how reliable the method you used for testing I would consider taking it to a mechanic or atleast consulting one.

John

[Brainchild]

Like I said earlier

Some of the local suppliers here do diagnostic checks free(Autozone, Oriellys) Might check the ones in your area, they can test it and tell you what it is without guessing.

I would check it out.

[Gomer]

I suggest www.doityourself.com they have forums there for specific categories of help... that is, you can use that site as well as techimo =)

[^hyd^]

not sure if this will solve the problem, but I always noticed a small boost in my 86 celica gts when I did this:

get some spray-type carb cleaner(make sure it's safe for oxygen sensors! I think they all are, but might want to check...) and an old toothbrush.
remove the rubber housing going to the throttle body, and if needed also remove the air cleaner cover.
spray some cleaner all over inside the throttle body and on both sides of the throttle-plate(butterfly valve), then start scrubbin!!! scrub all around the sides and both sides of the throttle-plate!! Once your happy that its clean, give a quik rinse with the cleaner and put it back together...

now, usually, if the throttle body was really dirty, after doing this the idle will come up a bit(from more/smoother airflow) so you'd have to disconnect the battery momentarily(30 secs or so) to reset the idle, but this will(should) also reset your code 11... so that parts up to you!! could hold off on the battery if you find the idle to be okay...
another note, for the first few seconds your exhaust will probably stink and may be blackish!

like I said, I'm not sure if this will solve your problem, but at the shop I worked at it was a part of every fuel-injectoin tune-up(when the throttle-body allowed it!!), and if it was real dirty it should feel a bit snappier... mine did anyways...

g'luck!!

I miss my celica... wish that damm bus driver had looked to the right before pulling out from that stopsign, then I might still have it!!

[Richard Cranium]

1. When was the last time the valves were adjusted.
Typical wear pattern is;
Intake valves close up, causing hesitation when cold.
Exhaust valves open up, causing clicking at idle, hot or cold.

2. Antifreeze inhaled into the motor;
This will destroy the Oxygen sensor the FIRST time it happens.
Make sure to use a Brand Name part on this car, no name stuff is junk.

3. Intake Manifold vacuum leak.
This confuses the mixture signal from the O2 sensor and can cause your symptoms.

4. Faulty TPS [throttle position sensor]
Sometimes it's simply a situation of corrosion on the contacts, this may NOT be visible but merely a coating of sorts that will not allow full voltage conduct.
You can check the TPS with a el-cheapo Volt Ohm Meter, make sure it's an analog not digital.
Hook it up and move the TPS slowly, the VOM needle set to Ohms will move slowly, not jerky. [Engine Off, Switch OFF]
Switch ON, set the VOM to volts and look for smooth rise in the needle.
The TPS is merely a variable poteometer[sp?] or varistor or trimpot.. A resistor that varys with pedal travel.

5. Look for cracked hoses going to sources of "Manifold" Vacuum
These will leak air in very badly during idle but less when you add throttle.
You can check for air inleakage with a propane torch.
Simply open the torch valve{DO NOT LIGHT THE TORCH} and sweep around the motor while at idle, when the propane is sucked in a vacuum leak, the engine will raise the speed.
Primary areas are the base of the Throttle body, the gasket area from the intake manifold to the motor, and all hose connectons.
Don't forget the Brake master vac, it may be leaking internally, usually you can hear them from inside the car if you stick your head under the dash while at idle and pressing on the brake pedal.

***NOTE***
Do NOT use the propane method if you have visible arcing of spark plug wires.
Listen for spark plug wire leaks, or better yet look at night for signs of visible arcing. .

6. Remove and replace all sensor wires checking for green or brown corrosion, brown is from oil and high resistance, green is from bi-metal battery action causing lack of contact.
CRC 2-26 is great to aid in getting electrical connections working again, read the label.
Wait the suggested 30 minutes for the stuff to evaporate or you may have tracking..