Squealing belt and stuff

'91 Civic hatchback, 5 speed

A couple of issues have cropped up recently, and I would like to hear your opinions on how best to resolve them. My main issue however is what I believe to be a squealing serpentine belt; but first, some background:

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BACKGROUND:
Other issues - related or not?

Main relay warm-start:
If the car is cold, or hot, it starts fine, but in warm weather, or if the engine has been running for just 5 minutes, then I turn it off, and then turn back on (ie. after a shopping trip), the engine will crank, but as long as it is warm (and the engine light stays on), the engine will not fire up. This is remedied by waiting for the car to cool down, or by hitting the main relay down by my fuse box with a stick until the engine light goes off and then the engine will fire up.

4th gear slipping:
Pretty self-explanatory. 4th gear has started to slip. I can either hold the gear lever in place in 4th, or just skip from 3rd to 5th gear.

Ok, now back to the belt issue. 80% of the time I fire up my engine, I get 2-3 seconds of squealing from the car. Occasionally a gear shift will also cause this, particularly if I shift too early and am running at a low RPM. The main issue however is the squealing caused by having my headlights on, and even sometimes just using my blinkers/brake lights. If I have my headlights on, I get squealing for 5-10 seconds, usually until I get into medium/high RPM in 2nd/3rd gear, then the squealing stops for a while, and then will usually restart when I am at a stop light or if I use my blinkers or brakes for more than a couple seconds.

I did get my timing belt and serpentine belt replaced about 6 months, or maybe 2-3,000 miles ago, although I think the mechanic who did the job was not terribly competent, as I had to take the car back after the work was done because my gas pedal was always on a little bit (he fixed that though). So here are my questions, in order of importance:

  1. Is the squealing caused by my serpentine belt?
  2. Is it still charging my alternator as it should?
  3. Can I just tighten, or grease up, the squealing belt, or should it be replaced? If replace: will labor be expensive, or is it easily accessible?
  4. How bad of an idea is it to not deal with this squealing belt issue, and just let it squeal at night? (I don’t often drive at night anyway).
  5. Is there any chance that this is in any way related to the main relay/4th gear slipping issues?
  6. Someone told me that once 4th gear goes, 5th gear will be next. Is my 5th gear likely to start slipping soon? :frowning:
  7. Any thoughts on my main relay? Good/bad idea to get a used one? Can I replace it myself, or should I have a mechanic do it?
  8. Thank you for your help, and please forgive my lack of knowledge – this is my first car, and my understanding of how it works is quite rudimentary, so I am giving as much information as possible because I don’t know what might be relevant.

The squealing belt could be a problem with the alternator. You run the risk of the alternator seizing and breaking the belt and stranding you. The belt should be replaced also as it is 25 years old. Or it could be just the belt. Get it checked by a mechanic.

This is a manual transmission?

If the squealing started after the serpentine belt was replace then it is most likely that is what is squealing. It is most likely too loose but could also be too tight. You should have that checked immediately so you don’t get stranded.

A belt squealing is indicative of a belt slipping.
A belt slipping is a belt being worn faster than it should (like sliding on your tires on full brake lock-up).
A worn belt will fail earlier than expected, sometimes suddenly.
3000 miles on a screaming belt is a LONG time.

If it’s a serpentine belt, it could be the belt, or the tensioner. As a general rule, if you replace the serpentine belt, you should replace the tensioner.

Does a 91 Civic actually have a serpentine? I thought it had older style, regular belts. If so, they’re adjusted by moving the components on the run (alternator, power steering, whatever), rather than a tensioner.

If you have to hit a relay until it turns off, have you tried replacing said relay? Are you sure it’s actually turning off when you hit it, or just it just seem like that’s what’s happening?

Gears: Do you mean the shifter pops out of gear (as in the shift lever)?

By your description, I assume you have a manual transmission. It is a separate issue. You can continue to skip 4th gear or get it repaired. If you plan to keep the car for a few years, get it repaired. At this age, you should consider rebuilding it or buying a rebuilt transmission.

The squealing is likely the alternator belt, too loose. (Your car likely has separate belts for the alternator, the power steering, and the AC, if equipped - not a single serpentine belt that zigs and zags to turn the pulleys on all these components.)

Since the squealing is related to how much electrical power you’re using, that’s likely due to a problem somewhere on the belt routing that involves the alternator. First thing, check and address the belt condition and belt tension. Since it occurs more when the ambient temperature is colder, my first suspicion is the belt is just a little too loose. Belts tend to tighten up with higher temperature, loosen with colder. If neither are the problem remove the belt and hand turn each of the associated pulleys and accessories (in the correct direction) and see if you notice any weird noises or they don’t rotate freely.

The 4th gear slipping problem, do you mean it won’t stay in 4th gear unless you hold it there, or the engine rpms increase but the car doesn’t accelerate in 4th gear. If the latter, that’s probably the clutch that is slipping.

Honda Civic main relays are well-known to be problematic, esp when hot, and the best solution is to just replace it with a new one.