I work on cars. AMA

[Anonymous]

Anonymous wrote:

Anonymous wrote:What's your take on electric cars from a maintenance perspective? Aging mother drives once or twice a week, and her current car is getting old. I was thinking get her an electric car since for her short trips, the engine will never fully warm up and get lubricated anyway if she had a gas-powered vehicle.

I like them, when they are used in the niches they are designed for. Your situation that you describe is perfect for an EV. Nissan Leaf is the one that c9mes o mind, since I’ve actually been in one. I liked it. And I generally don’t care for Nissan/Infinity, so that’s my highest endorsement.

Sorry, forgot the part about maintenance.

Well, they still need it for the standard wear items that need to be replaced as needed on any car. Tires, brake pads and rotors, wipers, etc. I’ve never worked on an EV, but I’d imagine there are service intervals that need to be adhered to just like in a gas or hybrid car, but different items. The manual will tell you. Trust it. It was written by the people who designed the car.

The biggest expense you’ll likely incur with a EV is battery replacement if you keep it long enough, OR, allow it to discharge completely and “brick” itself. And batteries are NOT cheap.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:I have a 2007 Saab 9-3 2.0T w/manual transmission and w/76k miles on it which I really love to drive, would like to keep it another 12+ years if I can. Some trim pieces here and there are falling apart, some issues with central locking and window regulator, but mechanically its been solid (minus throttle body replacement and coils failing....latter likely because its tuned to Stage 1 w/20-30 more HPs and bucket-loads of more torque).

What kind of preventive maintenance (in addition to schedule maintenance) can I do to make it last another 12+ years? If its inexpensive, I'd like to change inexpensive parts earlier/before failing to make it run well, like last year I had the O2 sensors replaced, and as for all other sensors, I disconnected them as many as I could and have them cleaned myself. I replace the plugs every 25-30k miles, perhaps overkill, but plugs turn black fairly quickly, perhaps because I don't drive often. Because I don't drive it much, when I do, I've started driving the car much harder (after a full warm-up of course).



Thank you for your contribution.

Wow, I haven’t seen a Saab in forever. They are truly a niche car now, the only people still driving them are people who WANT to. I’ve never worked in them. I do know that the shared a platform with Opel, and being a GM subsidiary, there are probably OTS GM parts (coil packs, lock relays, O2’s etc) that are the same part #. You’re a tuner, so you already know more about it than I do.

The biggest advice I’d give you or anyone with a turbo on a small engine is let it idle for about a minute (longer if you been driving it hard) when you parked, before shutting it down. Reason being, the oil stream that lubricates the turbo bearings also acts as a heat sink, carrying heat away. If you shut down the engine (and oil flow) before this residual heat has been removed, it cooks the remaining oil in the bearings to sludge. Like making a reduction in cooking candy. Thickens the oil up, which clings to the bearings, becomes sludge, and blocks further oil flow. Let it cool off for a full minute. Also, use only synthetic oil. No natural oil at all ever.

Lastly, remember this: there are only so many horsepower-hours in an engine before it fails. It’s like a bucket full of water. You can pour it out all at once, have crazy amounts of horsepower for a brief time, or you can trickle it out slowly, and have an underpowered engine that lasts almost forever. But the amount of horsepower-hours is the same for both cases.

Thank you for your reply, that was kind of you, much appreciated. Yes they are rare indeed, apart from my own, I see perhaps 1-2 Saabs on the road every month so. Thank you for the reminder on letting the car idle. The Saab has a variable/on-demand kind of turbo, so by the time I've left the highway, back on local road (where it rarely adds much turbo pressure) and in-parking lot, its normally been around 4-5 minutes. Not sure if you think this is sufficient for cooling, of you think an additional minute or two of idling post-parking would be recommended, would be grateful to hear your input.

Also thank you the horsepower-hour/"bucket full of water" analogy. Yes, I'm kinda aware of that, but was hoping Stage 1 (ECU reprogramming only, no other mods) would be "mild" enough not to "empty the bucket" too early. The failing/cracking coils were perhaps a result of this, but I know people do Stage 2/3 going north of 300 HPs which would stress the engine even more. In general, are there any particular parts of the engine (not specific to Saabs) which are prone to fail in high(er) powered (turbo) cars?

I forgot to mention, the only place in the area that I know specializes in Saabs is out in Virginia, on Rt 29 eastbound, in between Warrenton and Gainesville. I think it’s called S&S service.

[Anonymous]

Anonymous wrote:

Anonymous wrote:We have 2010 Honda Odyssey V6 engine with around 60,000 miles, during acceleration, especially with the engine speed is less than 2500 RPM, you can hear rings clanging sound. We've replaced the spark plugs which did not help, but then moved from using 87 octane to 93 octane fuel, plus using a fuel cleaner every 3-6 months, that seemed to have helped (75%) but not entirely. Any idea what is causing this, perhaps its the (lose) piston rings or engine pre-detonating a milliseconds to early, and if so, what can be done to remedy it, if at all?

A couple thoughts: it might not be knocking/pinging/predetonation. It could be lifter or valve noise from a stuck lifter or low oil pressure. But the fact that it cleared up partially with increased octane also might mean you’ve got two different things going on, knocking AND lifter chatter. The higher octane cleared the knocking, allowing you to hear the lifter chatter isolated by itself now.

Low rpm knock under throttle happens because you’re dumping maximum fuel air mixture volume into a cylinder that is still undergoing a relatively slow compression and firing cycle, compared to higher rpm. The slower compression stroke at low rpm gives the mixture more time to predetonate. Higher rpm means the compression stroke happens faster, and before predetonation can occur, the spark plug fires

If it’s lifter noise, ultimately that will likely mean a cyclinder head rebuild. It’s not the piston rings, although in much higher mileage engines, the skirts of the pistons can wear and create piston slap against the cylinder liner. But that’s not what this is.

Thank you for detailed reply. Forgot to mention that the pinging noise occurs mostly when a) going uphill and b) just before the car downshifts (ie engine is likely running at too low rpm for engine to be "comfortable"....once it downshifts and RPM goes up, the noise disappears). So if its lifter noise, I'm guessing putting Seafoam or Liqui Moly Pro-Line Engine Flush in crankcase a few miles prior to next oil change won't suffice?

[Anonymous]

What's the best place to go in DC for honest service?

Also, how do you know about DCUM?

[Anonymous]

Anonymous wrote:

Anonymous wrote:NP here. I just bought a used BMW 435i convertible (automatic). I was caught in 1.5 hours of stop-and-go traffic, and my right knee started to hurt. By the time I got home, it was killing me and I was actually hobbling for a day, and it hurt for a few days afterwards.

Since then, I've only used it for short trips or one longer one in good traffic. I feel a little bit of discomfort afterwards, but nothing big.

Sitting in my longterm Toyota Highlander SUV made me realize this is a whole different system for gas/brake. In the SUV, you are sitting as if at a dining room chair and the weight of your leg is pressing on the gas/break (like a piano lever). But in the BMW, you are really extending your leg almost perpendicular to the ground, and pushing out that way. Your bum is lower than your knee.

I googled but don't seem to be able to figure out how to make the seat more user-friendly....should I push the seat back far, or up close to the steering wheel, or what else should I do? I was thinking of putting a towel under my bum to raise me up some, but it moved and was uncomfortable...not sure if there is a product for that.

Anyways, any advice for me? It could be a website for ergonomics, or a product, or just seat positioning advice.

Thank you!

I can empathize. I drove a Ford Escape from an auction where I bought it, and it had what seemed like the most comfortable seat I’ve ever sat in. Two weeks later, I bought a Subaru Forester at the same auction, drive home the same distance, and it was agony. Same general type of car, same size, similar ergonomic layout and driving position, but totally different feeling seats.

This is one of the reasons people should ask to test drive a car over the weekend. You need to spend at least a couple hours in the seat to really appreciate whether you fit in the car or not. But dealers won’t usually go for it, and most people never ask.

I’ll freely admit that I’m prejudiced against BMW to begin with, so I’d never own one. The last dealing I had with a BMW was back when I was still a partner in my shop, and I bought a 2001 760iL for literally pennies on the dollar. It was a flood car, I bought it on a salvage title. My plan was to refurb it and sell it, making a tidy profit. I didn’t need to ask for much, as I only paid $600 for it. I figured I could get an easy $10k for it. So I needed to replace all the electronics, ECU, TCU and main wiring harnesses. I figured that would probably run $5000 or so, leaving me still up $4400. Not bad for three days of work. WRONG! The wiring harness itself - JUST - the harness, was almost $15,000!!!! So I parted the car out for wheels, tires, glass, doors and hood, and scrapped the rest. I still made money, but only a third of what I thought I’d make. And I’ve been sour on BMW since then.

I don’t know what to tell you that might help... me, I’d trade the car for something else. I drive way to much to be uncomfortable doing it. It’s not fun being in physical discomfort just because you like a car.

Good luck. Let me know what you end up doing.

Ok thank you. Ha! I'm biased against BMWs too, but it's the only convertible hard top with 4 seats on the market. I have to tell you, it drives like a dream. Anyways, I'm going to play with the seat position and I am borrowing my DH's little gadget (designed to prevent back pain but maybe it will work) and will keep experimenting. This has got to be a common problem so I just have to figure out what other folks have done.

[Anonymous]

I need mechanical advice! I have a 2004 Trailblazer that I think might have an electrical problem. Sometimes while driving, all the lights on the dashboard come on and all the gauges go to zero and the speedometer doesnt work and you can't take the key out of the ignition but you can turn the engine off. If we wait for awhile, it'll go back to normal. Any ideas??

[Anonymous]

You mentioned you go to Carlisle for the auction a lot. What are the pickings like there? I've traded in a few cars to dealers a few times, and my impressions was they keep the good ones for their own used car lot, and send all the bad stuff up to auction.

[Anonymous]

I have an ‘06 Toyota Sienna. Around 185,000 miles.

The air conditioner puts out somewhat cool/warm to hot air. Did a freon refill and it put out cool air for 1-2 days then went back to warm air.

What might be going on with it and how much would you estimate it would cost to fix?

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:We have 2010 Honda Odyssey V6 engine with around 60,000 miles, during acceleration, especially with the engine speed is less than 2500 RPM, you can hear rings clanging sound. We've replaced the spark plugs which did not help, but then moved from using 87 octane to 93 octane fuel, plus using a fuel cleaner every 3-6 months, that seemed to have helped (75%) but not entirely. Any idea what is causing this, perhaps its the (lose) piston rings or engine pre-detonating a milliseconds to early, and if so, what can be done to remedy it, if at all?

A couple thoughts: it might not be knocking/pinging/predetonation. It could be lifter or valve noise from a stuck lifter or low oil pressure. But the fact that it cleared up partially with increased octane also might mean you’ve got two different things going on, knocking AND lifter chatter. The higher octane cleared the knocking, allowing you to hear the lifter chatter isolated by itself now.

Low rpm knock under throttle happens because you’re dumping maximum fuel air mixture volume into a cylinder that is still undergoing a relatively slow compression and firing cycle, compared to higher rpm. The slower compression stroke at low rpm gives the mixture more time to predetonate. Higher rpm means the compression stroke happens faster, and before predetonation can occur, the spark plug fires

If it’s lifter noise, ultimately that will likely mean a cyclinder head rebuild. It’s not the piston rings, although in much higher mileage engines, the skirts of the pistons can wear and create piston slap against the cylinder liner. But that’s not what this is.

Thank you for detailed reply. Forgot to mention that the pinging noise occurs mostly when a) going uphill and b) just before the car downshifts (ie engine is likely running at too low rpm for engine to be "comfortable"....once it downshifts and RPM goes up, the noise disappears). So if its lifter noise, I'm guessing putting Seafoam or Liqui Moly Pro-Line Engine Flush in crankcase a few miles prior to next oil change won't suffice?

You can try it, but I don’t know if it’ll help or not. Honestly, it may go another 100,000 miles like that. I’d let it ride. When (or if, even) it stops running because the valves won’t stay open, then get it fixed. Price is the same either way. All the damage has already been done to the lifters, cam and everything, so it’s not like those parts are reusable anyway. When it needs it, it’ll be new cyclinder heads on both sides. Until then, I’d drive it

[Anonymous]

Anonymous wrote:What's the best place to go in DC for honest service?

Also, how do you know about DCUM?

Ask your friends or neighbors, or people with your make of car. They’ll know . They’ll also tell you who to avoid. I’d avoid dealerships if possible.


Daughter told me about it. She thinks I don’t have enough to do.

[Anonymous]

Anonymous wrote:I need mechanical advice! I have a 2004 Trailblazer that I think might have an electrical problem. Sometimes while driving, all the lights on the dashboard come on and all the gauges go to zero and the speedometer doesnt work and you can't take the key out of the ignition but you can turn the engine off. If we wait for awhile, it'll go back to normal. Any ideas??

Very common thing. More so with Jeeps for some reason, but any car can have this. Basically the dash instrument cluster is a self contained module. It literally plugs into a wiring harness and fits right into a recess in the dash. The contacts in the connector sometimes lose contact when they get jarred or hit a bump or whatever. If you slap the top of the dash cluster when it happens, usually they pop back on. The fix is take the dash cluster out, slightly bend all the contact pins -again SLIGHTLY, no more than a few degrees, barely perceptible- then add some dielectric grease in the female contacts, and put the whole thing back together. 2000’s Jeeps are very easy to do this on, I don’t know about Trailblazers, I’ve never had some apart for that problem

[Anonymous]

Anonymous wrote:You mentioned you go to Carlisle for the auction a lot. What are the pickings like there? I've traded in a few cars to dealers a few times, and my impressions was they keep the good ones for their own used car lot, and send all the bad stuff up to auction.

Yeah, that’s about right. The stuff at auction needs attention. Used dealers or wholesalers don’t wanna mess with a car they have to fix before selling. That’s a waste of money them. They don’t even staff a technician at most used dealers.

Which is why I buy at auctions. Because I can pay almost nothing for a car, literally like $50 more than scrap value sometimes, spend a few days fixing it, and turn at least a couple thousand dollars on it most of the time. The downside is I spend a lot of time waiting on UPS to drop parts off, and I have a lot of cars sitting on my property in various stages of repair, but my wife doesn’t mind. One of the benefits of having a big lot with a tall privacy fence.

[Anonymous]

Anonymous wrote:I have an ‘06 Toyota Sienna. Around 185,000 miles.

The air conditioner puts out somewhat cool/warm to hot air. Did a freon refill and it put out cool air for 1-2 days then went back to warm air.

What might be going on with it and how much would you estimate it would cost to fix?

Sounds like it’s got s slow leak of the refrigerant. Yours uses R-134A, you can get little do it yourself kits at auto parts stores. But just adding every few days is gonna cost out the ass pretty quickly.

If you’re up for trying it, you can buy a dye test kit. Basically a UV dye that you inject into the refrigerant system when you add R134. Let it run a few days until it stops cooling again. Then use a UV/blacklight flashlight, and look for the dye to show up. That’s where the leak is. Whether you can fix that or not is up to you though. Or take it to a trusted shop. They’ll do the same test

[Anonymous]

Have you ever known a technician who intentionally damaged a car that was in the shop for work? If so, what was their motivation?

[Anonymous]

Anonymous wrote:

Anonymous wrote:You mentioned you go to Carlisle for the auction a lot. What are the pickings like there? I've traded in a few cars to dealers a few times, and my impressions was they keep the good ones for their own used car lot, and send all the bad stuff up to auction.

Yeah, that’s about right. The stuff at auction needs attention. Used dealers or wholesalers don’t wanna mess with a car they have to fix before selling. That’s a waste of money them. They don’t even staff a technician at most used dealers.

Which is why I buy at auctions. Because I can pay almost nothing for a car, literally like $50 more than scrap value sometimes, spend a few days fixing it, and turn at least a couple thousand dollars on it most of the time. The downside is I spend a lot of time waiting on UPS to drop parts off, and I have a lot of cars sitting on my property in various stages of repair, but my wife doesn’t mind. One of the benefits of having a big lot with a tall privacy fence.

Could you please provide some more info about the Carlisle auction lot, city location, name of company (Mannheim?) and how best to be able to purchase a car from there? I believe one needs to go via a person of company licensed to purchase at car auctions, correct? I do small repairs on car myself so thought I'd take the risk getting a car from an auction.