Automotive Forums .com - the leading automotive community online! Automotive Forums .com - the leading automotive community online!
Automotive Forums .com - the leading automotive community online! 
-
Latest | 0 Rplys
Go Back   Automotive Forums .com Car Chat > Toyota > Celica
Reply Show Printable Version Show Printable Version | Email this Page Email this Page | Subscription Subscribe to this Thread
 
Thread Tools
Old 02-27-2012, 10:59 AM   #1
mannasugar
AF Newbie
 
Join Date: Mar 2007
Location: Rockwall, Texas
Posts: 60
Thanks: 1
Thanked 0 Times in 0 Posts
90 Celica misfire

I have a 90 Celica, 2.2, EFI, 5 spd standard, runs rough, I just bought the car for $900. It has a misfire, I was told it was the coil pack. I replaced the coil and it didn't help. One day the car would not start. I grounded the coil to see if I was getting spark (plenty of spark). I grounded a spark plug wire (no spark). I grounded the next spark plug wire (car starts). The car has not started about 6 times each time I ground the spark plug wire and the car starts. One time the car would not start by grounding the spark plug wire and it wouldn't start. I grounded the coil (no spark). I plugged everything back in and the car started. The car has power and takes off until I put my foot into it and it cannot burn the fuel fast enough and bogs down.
Check engine light is not on....
How do I check the ECM?
What could be other causes?
All answers are greatly appreciated.....
mannasugar is offline   Reply With Quote
Old 02-27-2012, 01:57 PM   #2
jgabranski
AF Newbie
 
Join Date: May 2011
Location: hudson, Wisconsin
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
Re: 90 Celica misfire

Whats your fuel pressure like with key on engine off?
jgabranski is offline   Reply With Quote
Old 02-27-2012, 05:13 PM   #3
mannasugar
AF Newbie
Thread starter
 
Join Date: Mar 2007
Location: Rockwall, Texas
Posts: 60
Thanks: 1
Thanked 0 Times in 0 Posts
Re: 90 Celica misfire

I took the fuel line off from the fuel filter and turned the ignition key on (no fuel, no fuel pressure).

Assuming it is the fuel pump....
What is the difficult rating for replacing a fuel pump in a 1990 Toyota Celica?

Is the control module saying "If you do not have any fuel I will not give you any spark?"
or

Do I also have ignition problems?

Thanks for your great question.....
mannasugar is offline   Reply With Quote
Old 02-28-2012, 08:48 AM   #4
mannasugar
AF Newbie
Thread starter
 
Join Date: Mar 2007
Location: Rockwall, Texas
Posts: 60
Thanks: 1
Thanked 0 Times in 0 Posts
Re: 90 Celica misfire

I received inaccurate information from Youtube. When I took the fuel line off from the fuel filter and turned the key on I got no fuel, when I cranked the engine over I got fuel. I do not have a fuel pressure gauge.
mannasugar is offline   Reply With Quote
Old 02-28-2012, 04:24 PM   #5
DeltaP
AF Enthusiast
 
Join Date: Oct 2011
Location: Ft Lauderdale, Florida
Posts: 953
Thanks: 13
Thanked 121 Times in 120 Posts
Re: 90 Celica misfire

If you're intent upon fixin this yourself you'll need a fuel pressure guage and know how to connect it to the fuel system. There should be a certain fuel pressure when the key is turned on and another pressure when the engine is running and it must hold a certain pressure for awhile when the engine is off. You'll also need some sort of manual to help ya troubleshoot and diagnose multiple problems.
DeltaP is offline   Reply With Quote
Old 02-28-2012, 09:19 PM   #6
shorod
SHO No Mo
 
shorod's Avatar
 
Join Date: Jun 2004
Location: Cedar Rapids, Iowa
Posts: 10,946
Thanks: 99
Thanked 350 Times in 344 Posts
Re: 90 Celica misfire

Were you always grounding the same spark plug wire to get it to start? If so, which one? And can you describe the process you were using the "ground" the wire? Normally grounding the wire would cause a misfire, not allow the engine to start. Have you pulled the spark plugs and checked the condition and gap of them? Was the car sitting before you bought it? Maybe the fuel in it is trash.

-Rod
shorod is offline   Reply With Quote
Old 02-29-2012, 09:04 AM   #7
mannasugar
AF Newbie
Thread starter
 
Join Date: Mar 2007
Location: Rockwall, Texas
Posts: 60
Thanks: 1
Thanked 0 Times in 0 Posts
Re: 90 Celica misfire

Rod,
The first time the car would not start, I wanted to check spark coming out of the coil. I was by myself so I used some speaker wire I have set up with alligator clips on the ends. I clamped the alligator clips to the coil wire and ran the wire to the car door hinge so that I could reach it and see it at the same time while I turned the key over (plenty of spark coming out of the coil). I pulled the number one spark plug wire off and ran my extension wire to the door, I held it close and the car would not start. I went to the number 2 cylinder and ran my extension wire and when I cranked the engine over it wasn't sparking, but soon after a couple of revolutions it began to spark and the car started. The car was running rough because there were only 3 cylinders firing.

Spark plugs are screwed into the heads which is ground. So, I don't know what you mean when you say "grounding a wire will cause a misfire". All spark plugs are grounded. The center of the spark plug is isolated from ground and the spark jumps to ground at the gap.
What does any fuel question has to do with spark?

Thank you
mannasugar is offline   Reply With Quote
Old 02-29-2012, 10:49 AM   #8
shorod
SHO No Mo
 
shorod's Avatar
 
Join Date: Jun 2004
Location: Cedar Rapids, Iowa
Posts: 10,946
Thanks: 99
Thanked 350 Times in 344 Posts
Re: 90 Celica misfire

Right, the spark plugs are screwed in to the grounded head, and normally a spark would jump from the tip to the grounded electrode. When you ground the spark plug wire, you are short circuiting the spark, so instead of traveling through the spark plug, it now travels through your ground wire straight to ground, and therefore that spark plug does not fire, causing a misfire. That was my confusion. The "ground the plug wire" trick is used to identify which cylinder is already misfiring, not to determine if you have spark or not.

So if I'm reading what you were doing correctly, you were not actually "grounding" (short circuiting the coil or plug wires to ground) the wires, you were using the speaker wire to route the spark near you so you could crank the engine and watch for spark to jump from the jumper wire to ground at the same time. You weren't clipping the wire to the door hinge, just holding it NEAR the hinge to watch for a spark to jump, correct?

So if you can confirm that you consistently have good spark from the coil, but not always good spark to the plug wires, that would suggest either a distributor cap or rotor issue is likely. You could also have bad spark plug wires.

You might start by performing a tune up consisting of wires, plugs, and cap and rotor. Assuming the parts you install are not defective, then you at least have several items in the electrical system that you can rule out as being the problem if they do not fix the issue.

The questions related to fuel are probably due to the unclear understanding of how you were confirming that spark was the issue.

-Rod
shorod is offline   Reply With Quote
Old 02-29-2012, 03:51 PM   #9
mannasugar
AF Newbie
Thread starter
 
Join Date: Mar 2007
Location: Rockwall, Texas
Posts: 60
Thanks: 1
Thanked 0 Times in 0 Posts
Re: 90 Celica misfire

Rod,
You are understanding what I was doing!
I know I have injector needs. I used different 2 cans of injector cleaner in my gas tank, which made a difference. I know I need a tune-up. I am short on cash and I do not want to purchase parts that I do not need. My confusion came when the car started from checking for spark. I didn't ground the wire, my apologies for the misunderstanding.
Why does the car start when I checked for spark by holding my jumper wire close to ground, assimilating a spark plug gap?
mannasugar is offline   Reply With Quote
Old 02-29-2012, 05:11 PM   #10
shorod
SHO No Mo
 
shorod's Avatar
 
Join Date: Jun 2004
Location: Cedar Rapids, Iowa
Posts: 10,946
Thanks: 99
Thanked 350 Times in 344 Posts
Re: 90 Celica misfire

The only thing I can think of is by forcing the coil to just a gap in the air versus in the combustion chamber with fuel, may have caused the rotor/distributor to arc and start making contact. It's purely a guess, but similar in concept to what can happen when there is a loose connection in a battery cable. Sometimes honking the horn at the same time you try to engage the starter will cause enough current to flow to get an arc going and maybe even some carbon tracing which will be more conductive than the other crap that forms over time on the rotor and distributor cap leads.

You could try wire brushing the rotor contact points and leads in the distributor cap to see if removing the more resistive corrosion will give you a more reliable spark. If so, then you know that starting with a new cap and rotor will not be money wasted.

-Rod
shorod is offline   Reply With Quote
Old 03-01-2012, 08:11 PM   #11
mannasugar
AF Newbie
Thread starter
 
Join Date: Mar 2007
Location: Rockwall, Texas
Posts: 60
Thanks: 1
Thanked 0 Times in 0 Posts
Re: 90 Celica misfire

I am planning on pulling my injectors to clean them.
What should I look for to determine if they need to be replaced or just a good cleaning will suffice?
mannasugar is offline   Reply With Quote
Old 03-04-2012, 10:57 AM   #12
mannasugar
AF Newbie
Thread starter
 
Join Date: Mar 2007
Location: Rockwall, Texas
Posts: 60
Thanks: 1
Thanked 0 Times in 0 Posts
Re: 90 Celica misfire

The car is running great, the only thing I have done to the car is use 2 different cans of injector cleaner in the gas tank. I went for a test drive yesterday and it has plenty of power. I had one stop and the car would not start. I used my jumper wire to start the car and it would not start. I checked for spark out of the coil and got no spark. I let it sit about 10 minutes and the car started.
I have 2 coils, neither of them would give me a spark.
Where does the coil get voltage from?
The ECM?
The battery is good and the alternator is good.
mannasugar is offline   Reply With Quote
Old 03-05-2012, 09:31 PM   #13
shorod
SHO No Mo
 
shorod's Avatar
 
Join Date: Jun 2004
Location: Cedar Rapids, Iowa
Posts: 10,946
Thanks: 99
Thanked 350 Times in 344 Posts
Re: 90 Celica misfire

The coil will get voltage from the battery, most likely switched by the ignition. The coil is apparently integrated in to the distributor cap on your car. The more likely culprit is the trigger to the coil, which comes from the ignition module. The symptoms you are describing (no spark after things warm up, requiring a cooling period before the car will start again) are pretty consistent with a faulty ignition module or pick-up coil for the ignition module.

-Rod
shorod is offline   Reply With Quote
Old 03-06-2012, 08:27 AM   #14
mannasugar
AF Newbie
Thread starter
 
Join Date: Mar 2007
Location: Rockwall, Texas
Posts: 60
Thanks: 1
Thanked 0 Times in 0 Posts
Re: 90 Celica misfire

Yes, the spark is supplied by the battery but it is controlled by the ECM. I am not familiar with an ignition module. I am sure both coils are good. The coil is mounted on the fire wall. The car has an igniter.
What does the igniter do?

The Typical Toyota Ignition System consists of spark plugs, ECM (engine control module), igniter, ignition coil, cap and rotor, ignition switch, fuse and battery. The electronic ignition system uses the Engine Control Module (ECM) for determining ignition timing (spark advance). The ECM determines ignition timing (spark advance) based on various input signals. Following input signals may be used: engine coolant temperature sensor, throttle position signal, oxygen sensor, engine RPM, vehicle speed sensor, A/C switch, brakelight signal, airflow meter, knock sensor, electrical load, MAP sensor and cranking (starter) signal. Input signals may vary on model application.

What is the Igniter?
mannasugar is offline   Reply With Quote
Old 03-06-2012, 08:53 AM   #15
shorod
SHO No Mo
 
shorod's Avatar
 
Join Date: Jun 2004
Location: Cedar Rapids, Iowa
Posts: 10,946
Thanks: 99
Thanked 350 Times in 344 Posts
Re: 90 Celica misfire

I did a little searching and found this article that seems to describe the Toyota ignition systems and indicates that the "ignitor" is the same as the ignition module. The pickup coil sends a signal to the ECM which then sends pulses to the ignitor, and the ignitor provides ground to the coil primary to cause the field to collapse and fire the spark plug.

If you happen to have access to an oscilloscope you could pretty confidently verify if the issue is the pickup coil, the signal from the ECU, the ignitor, or the coil. These pulses will be too short in duration to be picked up by a typical multimeter.

-Rod
shorod is offline   Reply With Quote
The Following User Says Thank You to shorod For This Useful Post:
mannasugar (03-06-2012)
 
Similar Threads
Thread Thread Starter Forum Replies Last Post
98 Dakota single cylinder misfire following overheating 98dak0ta Dakota 2 01-28-2011 02:02 PM
Multiple cylinder misfire codes Pokee Windstar 6 05-04-2010 09:10 PM
Celica 101's celica (WIP) nicecar Sketching and Drawing 7 10-25-2005 06:13 PM

Reply

POST REPLY TO THIS THREAD


Tags
coil , good , misfire , rough , runs
Go Back   Automotive Forums .com Car Chat > Toyota > Celica

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 08:26 AM.

Community Participation Guidelines | How to use your User Control Panel

Powered by: vBulletin | Copyright Jelsoft Enterprises Ltd.
 
 
no new posts