There is a blow off valve type sound coming from the engine and then steam coming out.

ANSWER : Let me address your mention of the A/C first because of the possibility of a refrigerant leak. Such leaks do create "steam clouds" like that you are describing but the leaks end VERY quickly because the refrigerant boils off violently as it hits the atmosphere. At any rate, IF the A/C system continued to blow cold air during this incident, that would mean that the A/C system is NOT the source of the leak.

If the A/C system did not develop a sudden leak, the likely explanation for the steam cloud is a cooling system leak. Such a leak can be addressed during a mobile visit from YourMechanic. You report an additional issue, though, which is the no-start condition. YourMechanic can diagnoses and repair that as well. Your no start condition could be due to a simple problem such as an old dead battery in need of replacement. If you want to do some initial work of your own, on the no start problem, just fully charge the battery, and once fully charged perform a load test on the battery to see if it is any good. Please let us know how we can assist you further on these two problems that you are having with your car.

ANSWER : On a 1998 engine with 147,000 miles, the noise could come from anywhere. I typically check the engine oil level when cool to verify it is correct. Then, I run the engine for 5 minutes, shut it off, and check the engine oil level again.

If after running it for a short time and the engine oil level is lower, then it is likely you have a sludge build-up in your oil return passages preventing oil from draining back to the oil pan. If so, maybe an engine oil flush is in order. At the mileage, sometimes an oil flush may do harm to your piston rings or may help. You never really know.

If the oil level is correct after running the engine, you should have an oil pressure gauge connected to the engine to verify that it is within specifications to factory numbers to verify the oil pump is working properly.

An engine tapping noise could be anything from connecting rods on the crankshaft to an engine valve lifter. If the noise is a knock-knock in a repetitive motion at a slow speed, I would suspect lower engine problem, like a connecting rod (which requires a complete engine rebuild). If the noise is at a higher frequency, then I would think you have a valve issue which could be repaired at a much lower cost.

Based upon mileage, the feeling of how the engine runs, engine codes (if any), and an unknown level of maintenance, it is difficult to determine the exact issue. You may need an engine repair, a new engine, more oil, an oil pump, or just live with it. I’d have a certified mechanic take a look at it to diagnose and fix the sound that’s coming from your engine.

ANSWER : Hey there. If the engine electric cooling fan is not turning on, the reason has to be determined. The fault could be due to a bad electric motor, a bad coolant temperature sensor, a failed relay, or even a wiring/fuse problem.

To resolve cooling system problems, one typically starts with a cooling system diagnostic. If the diagnostic establishes that the electric fan motor itself is bad, replacement of the fan motor is a straightforward procedure that is done by a mobile professional.

The leak and steam that you are seeing might be a consequence of the engine overheating because if the fan is not operating not enough air will flow though the radiator at low vehicle speeds. Once the fan is restored, the rest of the cooling system can be checked out to be sure that there are no actual leaks and that your car engine’s operating temperature is within normal limits. If you want to have this taken care of, a certified professional from YourMechanic can come to your car’s location to diagnose the overheating issue and assist with repairs.

ANSWER : Hello – the P1346 problem code you have indicates a camshaft timing problem (variable valve timing to be specific), and is at least part of the cause of low power. The cams are out of time, relative to the crankshaft. The hissing sound from the throttle body area is likely an air leak from a hose, or some other portion of the air intake. The tapping sound could be a variety of faults, worn/leaking hydraulic valve lifter, worn cam, piston slap, etc. I recommend a timing belt service to get the cams properly timed, performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

ANSWER : The oil pressure warning light will come on if oil pressure falls below a safe threshold. It is possible for there to be plenty of oil in the engine but, due to a fault in the oil pump, oil pressure falls too low. Oil pressure can be tested using an external gauge, connected to an access port on the engine block, but if pressure is truly low obviously running the engine even during the test contributes to the damage. If you do use an external gauge, just make the test as brief as possible. If oil pressure is low, it is possible to install a new oil pump if the pump is defective but of course there is the possibility that the engine has already incurred some damage. The recommended service to request is an oil pressure inspection/diagnostic and the responding certified mechanic will let you know why the light is on and what the required repairs will be. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

ANSWER : If air is getting to the valve but not coming out, odds are yes the valve is bad. Unfortunately there is no rebuilding kit for them. It most likely will have to be replaced then the entire system will need to be checked for any other leaks or faults.

ANSWER : Hello there, thank you for asking about your 1992 Isuzu Pickup. A professional will have the correct equipment to read OBD1 codes. Retrieving the diagnostic trouble code(s) is the first place to start when diagnosing your vehicle. Increasing RPMs changes engine load, which can in turn affect many different sensors and components, causing the Check Engine Light to illuminate. The only way to narrow down the options and find the culprit is through in person diagnosis with an OEM compatible scan tool. A certified technician from YourMechanic can retrieve the OBD codes at your home or office.

ANSWER : The noise could be due to an exhaust leak although it is also possible that a failed wheel bearing could cause enough "rumbling" to sound really loud. If you request a vehicle noise diagnostic the origin of the noise will be pinpointed and the certified mechanic will let you know of the required repair and the cost. The power steering leak is probably not related to the noise (unless the fluid level has fallen low enough to cause pump noise). Power steering leaks can be a fire hazard though (if the leaking fluid contacts a hot engine part) and so you should have the leak repaired. The service to request is a power steering system inspection – leak diagnostic. If you request these services, a certified Mechanic, dispatched by YourMechanic will come right to your location and get these problems fixed for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.