Carbon buildup on the top of the piston is common. Over time this can lead to symptoms varying from light ticking to knocking noises. Performing a fuel injector cleaning procedure can often help the condition by removing some of the piston top deposits.
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Repairpal verified 1990 Chrysler New Yorker problems
Various driveability issues may be the result of low fuel pressure due to a failed check valve inside the fuel pump. If this is found to be the case the fuel pump should be replaced.
Engine oil leaks may develop from the following areas: Valve cover gaskets, cam plugs at rear of the cylinder head, cam seals, front crankshaft seal, and the oil filter bracket. Leaking seals and gaskets should be replaced. Due to mis-machining of the mating surfaces, as special gasket is required to correct the oil filter bracket leak.
3.0L engines may develop an excessive oil consumption issue. Blue oil smoke may be noted from the exhaust during deceleration conditions (high engine vacuum). Our technicians tell us that this condition can be caused by valve guides dropping out of position. Updated valve guides with a revised snap ring grove are available to correct this issue.
A high pitched whistle type noise may be noted from the engine at idle. The repair for this condition can include replacing the idle air control motor with an updated part.
A hard or no start condition may be noted in low ambient temperatures which can be caused by corrosion at the engine coolant temperature sensor. If this is the case the coolant sensor and its pigtail should be replaced with updated parts.
A slight engine knocking noise may be noted on light acceleration after a cold start. Our technicians tell us there is powertrain control module (PCM) software update available which may correct this issue.
On higher mileage vehicles timing cover oil and coolant leaks, front crankshaft oil seal leaks, and valve cover gasket leaks are common. Our technicians recommend replacing the timing chain and gears if the timing cover is removed for resealing. It is also recommended to inspect the oil pan gasket and replace the drive belts and tensioners at this time.
A tappet/lash adjuster noise may be noted from 3.0L engines. Proper testing of the valve lash adjusters should be performed before replacing any parts. Our technicians tell us a full crankcase of clean engine oil is necessary before determining if any lash adjusters are bleeding down and causing a noise concern.
A faulty transaxle input speed sensor can cause the automatic transmission to default into a "limp-in" mode. Our technicians tell us there is an updated input speed sensor available to correct this condition.
The connector on the input and/or output speed sensors on the automatic transmission may become damaged causing intermittent loss of speed control. Our technicians tell us there are wiring repair kits available to repair this issue.
Automatic transmissions can exhibit a variety of shifting and noise concerns due to failure of internal components. Our technicians tell us that due to the fact numerous updated parts are available for this transmission a complete inspection of all internal parts should be performed if the transmission is disassembled for overhaul.
The anti-lock brake (ABS) warning light may illuminate. This condition may be caused by a faulty electrical connection at the ABS system and/or warning light relays. Our technicians tell us there is a revised wiring jumper harness available to correct this concern.