1999 Pontiac Grand Prix GTP Problems
RepairPal has identified the most common problems with the 1999 Pontiac Grand Prix GTP as reported by actual vehicle owners. We'll tell you what the problem is and what it'll take to fix it.Refine by vehicle
The intake manifold gasket may develop and external engine oil or coolant leak. In some cases, an internal coolant leak may occur causing coolant to mix with the engine oil. Running the engine with a coolant/oil mix may result in engine damage. Replacing the intake manifold gasket should correct this issue.
The serpentine belt tensioner pulley may wear out. Our technicians tell us that in order to get a new pulley from General Motors you must purchase a complete belt tensioner assembly.
The crankshaft position sensor, ignition module, and/or powertrain control module (PCM) may fail resulting in illumination of the Check Engine Light with ignition system related fault codes stored in the PCM. Patience is necessary when dealing with this specific situation as normal diagnostic procedures are not effective. In many cases, the best option is to replace parts, one at a time until the fault is corrected.
An automatic transmission fluid leak may develop from the rubber section of a transmission cooler line. In some cases the rubber section of hose can be replaced. In others, the complete cooler line must be replaced to correct this type of leak.
The EGR tube may develop an engine vacuum leak causing the Check Engine (SES) light to illuminate.
The intake manifold gasket may develop external engine oil leak. The manifold gasket will need to be replaced to correct this issue. RepairPal cannot confirm a recall for this concern on these models.