Having problems with your 1991 Volkswagen Jetta ?
1991 V.W. jetta 2.0 16v
\015 Not passing emissions. Replaced o2 sensor,exhaust system, air filter, cap, rotor, wires and spark plugs. Car has under 100,000 miles, does not smoke and has a little black residue on the exhaust tips.\015
Could be a number of things like air leak on the intake , cat in the exhaust , exhaust blowing or not sealed properly , map sensor ( if it has not got one ) then maf sensor , coolant temp sensor . Have had it plugged in to diagnostics ? There may be fault codes to give u indications of problem
Check o2 sensor wiring down back of eng and also for broken wires there can lean out w/hex t handle at fuel distributor ontop of air box
Repair Help & Product Troubleshooting for 1991 Volkswagen Jetta
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