GEN 3 Ignition Wires & Distributor Cap/Rotor

[dz63]

I have '96 Camry 2.2L I4 auto with original (ie. 12 year old) ignition wires, distributor cap and rotor. Currently, engine is running smoothly. Replaced the plugs with NGK platinum recently. Primary concern is fuel economy. In your opinion, would changing the ignition wires, distributor cap and rotor increase my fuel economy? Any guesses at how much? Or should I just leave this stuff alone as there are no problems?

I have read on TN that NGK is a good brand for igntion wires. The NGK TE62 wire set is $43 delivered to USA address (Rock Auto). Any opinions on distributor cap and rotor brand names? There seems to be many choices on distributor caps and rotors such as Airtex, Japan, AC Delco, Standard.

If you have an opinion, on the above, I am interested to hear it.

Thanks!

[Albuynp Ryeno]

If th car is that old a tune up might be a good idea.

My 98 5s-fe always had pretty good gas milage. I did a tune up

Fuel Filter
Air Filter
PCV Value
Spark Plugs
Spark Plug wires
Seafoam in brakebooster n fuel tank
Lucas fuel injector clean
Also I cleaned the throttlebody

The car is distributor-less so i didnt need to replace those parts. And its getting really good gas milage lately. BTW I used dealership toyota parts for everything.

[Mike Gerber]

If I were going to replace the distributor cap and rotor, I would go with Toyota OEM. The others just don't seem to last as long. As far as wires, I wouldn't replace them unless you are noticing a problem. All these things can be replaced, but you will not notice much of an increase in fuel mileage, if any IMHO.

PS: In the future it would be a good idea to include mileage on the car when asking about replacing items like these.

Mike

[dz63]

Mike - appreciate your candid response. 120K miles on it. I am not really interested to replace them if it won't do much to improve FE.

[Albuynp Ryeno]

Originally Posted by dz63

Mike - appreciate your candid response. 120K miles on it. I am not really interested to replace them if it won't do much to improve FE.

Have you opened up the cap n rotor, to check if they still look good?

As for the wires i would personally change them, actually i did change them on my car. Your from ontario right? Thats basically the same climate as my 98 since it was from michigan. In the winter the wires are gonna contract and expand a lot since when the temp drops they r gonna kinda freeze. If you leave a power tool outside in the winter or a garden hose, you'll see exactly how stiff they become. That contraction and expansion are gonna cause more wear n tear then usual.

I would also clean the throttlebody if you havent. Its super cheep all you gotta buy us one can of throttlebody cleaner or seafoam and use an old toothbrush.

[dz63]

Albuynp - thanks for your responses. Throttle body was cleaned by garage mechanic two years ago when the car was intermittently stalling at idle. It solved the problem. I do have a can of kleen-flo air intake system cleaner, so I could do it again. I am curious to know how cleaning a throttle body improves fuel economy? Can you please explain?

[Mike Gerber]

The spark plug wires on my 94 Camry 4 cylinder, 5SFE engine, with 87,000 miles on it are still original. I do not see or feel any signs of deterioration, so I am leaving them alone. I live in the Chicago area so the climate is roughly the same as the Toronto area. One quick and easy way to test your wires is to spray them down with water from a plant mister in a dark garage. Now rev the engien a bit. Do you see any arcing to ground (sparks)? Does the car start to misfire? If not, the wires are probably OK for now. You can still change them if you like for your peace of mind. They are not really that expensive. Again I would stick with Toyota OEM wires if you choose to change them.

I am not sure that cleaning the throttle body improves fuel economy (I have never seen any real proof one way or the other), but it does make the car idle and accelerate smoother, so it is a good idea to clean it regularly, IMHO; especially since it is so quick, easy and cheap to do. Since you had a stalling problem, I would pay particular attention to spraying the cleaner liberally in to the square or diamond shaped hole in the base of the throttle. That hole leads to the idle air control valve, where the stalling problem you had probably existed. Then clean the rest of the throttle body while the cleaner soaks in the idle air control valve for a few minutes.

Mike

[dz63]

Mike - you are the best! I appreciate you investing the time to explain how to check the ignition wires and also where to direct my cleaning efforts when cleaning the throttle body. If you can spare the time, I would appreciate to know what the idle air control valve does, what the diamond shaped hole is for, why the car runs rough when this gets dirty and how does it get dirty in the first place?

My '96 Camry is pushing 12 years old and is starting to rust around the wheel wells due to all of the salt that they throw on the roads here in the winter. I am not interested in throwing money at this car unless it is absolutely needed. I am planning to change the timing belt myself at the end of this month. Also need to replace two broken interior door handles as well as one broken sun visor (minor items). Will pick up the parts in the USA at the end of this month. We get severely raped in Canada for auto parts. If we order from the USA, the brokerage and duty to get things across the border occasionally exceeds the value of the goods. It really sucks.

On another note, I have to pull my emergency brake handle up about 7-8 clicks before it grabs, so I am planning to crack open the rear drum brakes and take a look. Minimum clean up and lube the adjusters, but maybe replace the shoes and machine the drums this time - not sure yet. The rear shoes are the original, and the drums have been off once for cleaning but that it all. Also, my upper rad hose is collapsing when the engine cools. I think this is a simple radiator cap change. Planning to service the rear brakes after I get the timing belt done.

Hope to keep the Camry for another 8 years if the body can just hold out that long. The Tercel is pushing 17 yrs and it just won't die...I really like Toyotas!

Thanks once again for your comments. TN forum rocks. Everyone on here is genuinely helpful and I have learned a lot reading other's posts. Wish I would have found this forum years ago.

[Kep]

On the emergency brake, how often do you use it? For drum brakes, Toyota uses an automatic adjuster that actuates each time that you use the parking/emergency brake. If you don't use it often it doesn't have a chance to keep adjusted. I'm not sure if it is the same for the disc/drum combos. You may be able to repeatedly actuate the parking brake (full up, full down, etc...) and see an improvement. Otherwise you may have to pull the drum and clean out the mechanism to get it working again.

+1 on what Mike said about the wires. You can also test their resistance values (under 20k ohms) and that of the center distributor post.

Fuel economy is helped by a smooth running engine. That means sensors giving the correct information to the ECU and fuel and air being delivered to the cylinders properly. Anything operating poorly in that chain can effect the mpg. You might also want to check the O2 sensors, air filter and vacuum lines.

Luck,
Kep

[dz63]

Kep - thanks. Use the e-brake every time I park. I think the adjusters are gunked up. Does the resistance in the wire go above 20K ohms if it is bad? Original O2 sensor. Is there any way to test it?

[Kep]

If resistance in spark plug wire (or center post of distributor) is over 20,000 ohms they should be replaced.

There are ways to check and inspect the O2 sensor with an ohm meter and visually. I have asked Doctor J if he knows if his method for a 3SFE OBDI port would work for the 5SFE but I haven't heard back from him yet. I just sent him a PM. I'll try to post his answer.

Kep

[Mike Gerber]

"If you can spare the time, I would appreciate to know what the idle air control valve does, what the diamond shaped hole is for, why the car runs rough when this gets dirty and how does it get dirty in the first place?"

In simple terms the valve allows more or less air in to the system to help control the idle speed. I believe the colder the engine is, the more air is allowed to go in to the throttle body. The rest of the system makes the fuel mixture richer to compensate for this increased amount of air. This helps raise the idle of a cold engine.

The diamond shaped port leads from the throttle body down to the idle air control valve underneath the throttle body. It's the passageway between the two systems.

The car runs rough because the correct amount of air is not allowed to pass through to the throttle body. The valve simply get's gunked up. When cold, it may not allow a fast enough idle. When warm, it can cause the car to die at idle.

The throttle body get's dirty because the engine's polution control systems recirculate unburned hydrocarbons back through the throttle body to be reburned again by the engine. Some of these unburned hydrocarbons also contain bit's of engine oil. Mix this engine oil with dirt from the incoming air charge going through the throttle body and you get dirty gunk everywhere inside the throttle body. This gunk also get's down in to the idle air control valve via the port mentioned above. Cleaning these things as part of routine maintenance, keeps the car idling and accelerating smoothly.

Mike

[Kep]

OK, Doctor J replied that the method that he described on the following thread:
'89 Camry 2.0L getting 20MPG?! should work for the pre-cat O2 sensor on 4 cyl OBDI models. I am pretty sure that my 1995 5SFE Gen 3.5 is an OBDI vehicle. If yours is not, it wouldn’t work.

Originally Posted by Doctor J

With engine idling at normal temperature[ fan cycled once] in the diagnostic connector ,
Jump T and E1 terminals, increase rpm to 2500, at this speed using analog voltmeter set at 10 VDC attach the positive probe to Vf terminal and negative probe to E1 terminal or ground;
The needle must fluctuate between the 5and 0 more then 8 times in 10 second period
If mixture normal and O2 sensor is working

This seems to be a welcome answer to a sensor that I previously thought was difficult to test.

Other points that I have read about O2 sensors are that they often fail because they get gummed up with silicon (wrong sealants used for gasket material is often the culprit) or with carbon (too rich a fuel mixture being used because of some other problem) or the exterior vents getting clogged up from dirt & oil. These problems can often be fixed by cleaning the O2 sensor by burning off the contaminant on the hot side with a propane torch or simply cleaning the ambient portion with a brush and pressure air. Unfortunately, O2 sensors evidently deteriorate with age as well. I guess that these must be replaced. If you decide to replace check out before you buy. There are generic versions that have to be modified to wire in and OEM compatibles that plug right in.

This is all hearsay, if anyone else objects I would likely give them more credence. But I think it is correct .

Kep

[dz63]

Kep - thanks for gathering the info on the O2 sensor. I have tucked this little nugget away in my favorites for when I have some more time to "play".

Mike - great explanation like usual. To summarize, the IACV lets air into the throttle body through the diamond or square shaped hole in the bottom of the throttle body, when the engine is at idle.

If the hole gets gunked up with oil and dirt, no air can pass and the engine runs rough at idle. To fix the problem, you dissolve the gunk in the hole with throttle body cleaner. After allowing it to soak for a few minutes, you fire up the engine and it sucks air throught the passage way and any residual TBC and gunk gets sucked into the engine and burned off. Then presto - you get a smoother idle....is that about right?

[Kep]

The "presto" part varies inversely with the severity of the "gunk"

Kep