Question to the Experts

I have a1993 Camry 4cyl with 200,000kms that seems to have a lot of vibration comming from the engine when I'm stopped at a traffic light. The steering wheel shakes and the dash also rattle a bit.I've had the car since new and before when it was newer you couldn't even tell the engine was running. The car is maticulously maintained and I just got installed a new timming belt. Any ideas on how to restore it to the smooth running engine it once had?

Reply to
SAM M.
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In news:ZyeWb.5983$ snipped-for-privacy@news20.bellglobal.com, SAM M. being of bellicose mind posted:

ALL four cylinder engines with automatic transmsissions do this. When the car is new, the motor mounts are more resiliant than when they've got 100k miles on them. You can spend the bucks to have the side motor mounts replaced (the two that secure to the side of the engine ... not the ends).

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- Philip @ Maximum Torque RPM
Reply to
Philip®

You have idle speed set at correct RPMs? If so replace the motor mounts - there was even a TSB on the mounts and they were updated with a new part number - think there is an lower (called a hydralic mount) and an upper one (called a torque mount - its dog bone looking--- check it for cracks). The upper one is snap to replace the lower more work. There are side ones to but suspect the others are worn first.

Reply to
Wolfgang

I don't claim to be an expert, just like to keep the Camry in good condition. (1994 4 cylinder). Noticed the steering wheel bouncing up and down at stops in Drive, and didn't seem "normal." Have been unwilling to replace motor mounts for this - and may have already been done by prior Owner - "dog bone" upper mount has been changed. Here's my suggestion. (I checked the steering wheel yesterday, and it doesn't move at idle stopped in Drive anymore, although one can still feel some vibration, it does not seem overly excessive). Now the "experts" may disagree with me here, but this is my understanding. When the engine is turned off, if there is even the slightest leak at the tip of the fuel injectors, the fuel can leave an slight accumulation of "gum" or "varnish" as residue, that, over time, can partially obscure the injector spray pattern. Many have said that by using detergent gasoline, this is avoided, yet I have seen improvement in my vehicle and a family member by using Red Line complete fuel system cleaner.

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The first application will clean the injectors, which can result in improved power from the engine. The description on their site makes sense to me. They say the oxygen sensor signaling the electronic control module controlling the fuel injector spray duration takes an "average" reading at the exhaust manifold, then adjusts all injectors to normalize the reading at the O2 sensor. The Red Line CFSC contains high temperature detergents, and synthetic upper cylinder lubricant. The detergent can (they claim, and show test results on the site) actually remove carbon deposits from the intake valves. Their description, which makes sense to me, is that when the valves are hot, gasoline can leave a residue over time that accumulates. By using CFSC regularly (a small amount each tank full as indicated on the side of the bottle - roughly 12 applications per one bottle), these deposits on the intake valves can be cleaned over time. This improves engine response (power) and also, (back to your original question) improves smoothness, noticeable at idle. It does take a number of miles to clean the intake valves though. The Red Line charts show 10,000 - 20,000 miles. So be patient. I am quite sure you will see an improvement. Also, check the spark plug wires with a digital multimeter, or ohm meter to insure resistance for each is less than 25K ohms. If resistance is too high (two of mine read "infinite" resistance) that will also cause rough running.

Reply to
Daniel M. Dreifus

In news: snipped-for-privacy@posting.google.com, Daniel M. Dreifus being of bellicose mind posted:

Since your initial evaluation is subjective AND since you did not remove the injectors as a group and performed a spray pattern test before using a fuel additive ... you've only rationalized what good the Redline product did. :^) Intake valve stem accumulations are also highly unlikely in engines where the injector spray can directly hit the underside of the intake valve and where valve guide seals are still good.

Regarding the spark plugs, their resistance varies depending on classification "suppressor" or "resistor" the former being a higher value. 25k ohms is a lot and "open circuit" suggests a gap inside the insulator where a resistor used to be. This is no good for obvious reasons.

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- Philip @ Maximum Torque RPM
Reply to
Philip®

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