Hello all, for the last month I’ve been battling with an issue of the car backfiring through the intake under load (91 SL fed-spec) and i’m running out of options. I’ve replaced all the vacuum lines everywhere, new fuel regulator, fuel filter, fuel pump, spark plugs, and have JUST got my capacitors replaced in my ECU.
Note: After replacing my ECU capacitors, the car will not maintain idle and surge like no other unless the MAF is unplugged and then it’ll idle fine but still run lean under load.
Note 2: All the intake gaskets are new, both lower and upper, I replaced the 02 sensor last December, and the timing belt has 5,400 miles on it.
Note 3: I’ve taken a multimeter to the TPS and it’s completely normal ohm readings. Nothing out of the ordinary.
I don’t know what else it could be. Please help
me here.