Rshort4747
Newbie
I’ve always been told if you have a miss under power it’s the spark plugs. If you have a miss at idle it’s plug wires. Does this hold true to a 98 throttle body Chevy? I don’t have a constant miss only intermittently at idle.
Engine misd
- Thread starter Rshort4747
- Start date
Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
Rshort4747
Newbie
No I haven’t but it’s only maybe 2 months old.
Rshort4747
Newbie
5.7
Rshort4747
Newbie
Could a dirty mass air cause it?
I hear it can but if that's the case get some mass air flow cleaner and clean it. Allow to dry before reinstalling it. Also are positive you don't have a vacuum leak?. Last some times fuel injectors can have build up. That's why I asked about fuel pressure. So depending on what's new on your truck. I would confirm each injector pushing out the same amount of pressure. You need to have a real scan tool that has a fuel pressure balance test.
NOT
EVEN
CLOSE
for any engine, let alone a "98 throttle body Chevy".
WHAT is a "98 throttle body Chevy"?
Misfire can be any one of two dozen things, or some combination.
Connect a scan tool, find out which cylinder(s) are misfiring. Look at the data stream for clues--short- and long-term fuel trim, O2 sensor readings, MAP voltage, and all the other sensors and outputs.
If all else fails, a cylinder-balance test is in order.
I had to explain to my wife why I was laughing so hard. Thanks for that.
Rshort4747
Newbie
You may have something there with injector pressure being off. This engine was swapped with another 5.7 and the guy had to use the old intake. So fuel pressure at injectors could be it because it was doing this with the old motor. I’ll clean mass air flow valve and see if it changes anything. Thanks for your help.
