99 OBW missing while brake pedal presssed

[twoblacklabs]

OBW. Can't figure this one out. While at stop lights, with brake pedal depressed, there will be an intermittent miss, no set pattern. If shift into neutral or park, 95% of time, missing will stop. On occasion, the miss will occur whether shifted into park or neutral.

 

Plugs, plug wires replaced.

 

Any suggestions?

[nipper]

Lest start out with two things. What is your alt output under this condition. Next does your brake booster have a vac leak. Thats the simple things.

 

Next spray some water on the coil pack and check for sparklies.

 

How old is the timing belt, and more importantly how old are the tensioners and idlers?

 

 

 

nipper

[OB99W]

OBW. Can't figure this one out. While at stop lights, with brake pedal depressed, there will be an intermittent miss, no set pattern.[...]

Is the idle different (speed, quality) if rather than using the service brake pedal, you apply the parking brake?

[twoblacklabs]

There is no ammeter so I'm best guessing on the output of the alternator. The lights don't dim when this happens, either dash or headlamps.

 

Original T-Belt, it's never been done and it's way past time. 146,000. Plan on doing it very soon (in between short paychecks). Wasn't sure if this was sign/symptom of T-Belt failure, or those items usually changed along with the T-belt.

 

Will spray water on coil. Never done that so not sure what to expect.

 

Thanks for suggestions.

[nipper]

You just answered your own question. You may have a failing tensioner or idler. You are playing with fire. There is a huge diffenrce between a timing belt job with all the parts and rebuilding your cylinder heads. It shows up under light load causing a miss or rough running. Skip the coil test for now, as either way you need a timing belt like yesterday.

 

 

 

nipper

Edited February 26, 2010 by nipper

[twoblacklabs]

Thanks again for all the help. Was afraid it was nearing time but wasn't sure what the idler pulleys dying would effect the combustion/delivery of power.

 

I am going to do it myself. Not afraid of the challenge. Developing a list of parts to buy is different story. Finding "Kits" of various components with various prices. Where is the best overall kit/price supplier? Budget is always a huge consideration and I don't want to buy junk. Will order online versus autozone if prices and parts are better. Plan on resetting oil pump gasket, replacing waterpump, thermostat, etc along with necessary gaskets and 0-rings.

 

If there's detailed up to date grocery list with price and vendor's contact info, That would be great also.

 

Thanks.

[MilesFox]

Timing belts are easy enough to do. I suggest NAPA. a timing belt kit with 281 tooth Gates belt, new style tensioner, and all the idlers is just under 300 bucks for the set. cam seals are 4-7 bucks apiece. if you order them individually you will likely get a part from japanese manufacture.

 

the belt is easier to put on first before bolting on the tensioner. the driver side upper cam may seem half a tooth off, but this is ok with the slack in the belt

[Cougar]

Like Nipper, I was thinking of the brake booster and a vacuum leak also. It may be a good idea to check the vacuum using a vacuum gauge to check for a sticky valve also.

[twoblacklabs]

Several months later.......

 

Finally getting around to changing the belt. Time and money were both tight so it just sat with only a few local miles driven.

 

In the meantime, I have posted a detailed thread on another forum[/url] as this site was down for a few days. Click here to take a look.

[Olnick]

Way to go! I enjoyed your post on the Outback board. Isn't it great when you're not under the gun to get 'er done? It really makes the work enjoyable, plus the great feeling of knowing you are being thorough in the effort.

 

Good luck on getting her all buttoned up.

[twoblacklabs]

Thanks for the comment. Here's the post of which he is referring.

 

It's back together, finally. So far, no hesitation. Hopefully, problem solved.

[Mike104]

I liked your How to Thread as well. Your experience is generally how my car maintenance items run. Just a simple job turns into a learning experience. Hopefully you will remember what you learned for the next time. Thanks for taking the time to post photos and your experience. It may save someone else some grief!

[Fuzpile]

I followed your post back into the other board because it was interesting seeing similar situations. Yes the plugs really need be out. I wasn't doing a 4-cam but it was confusing at times, those different marks. The other engines I was used to, TDC was paramount yet these marks didn't agree with that. I had a soft alum rod stuck in #1 as a gage,and when it wasn't getting pinched under a valve I began to see they were telling you to align like -hey forget what you know, this is Subaru land-. The reason being that the valve springs force the cams to different positions as soon as tension is relieved.

So they tell you another place to align everything to the belt. In the end,if correct hand rotation should show all the TDC marks line up but the belt marks are irrelevant.

[logic23]

if you are real strapped for cash I have a bunch of good lightly used 2.5 dohc timing belts, pulleys etc off low mileage engines that had blown headgaskets. I could put together a cheap care package.