I30 issue after starter replacement

[snipes1259]

I have a 1998 I30 that had its starter die on me last week. I replaced the starter and the car starts now, but when I reach around 20-25 mph the engine seems to hesitate and the whole car becomes a bit jerky. At any speeds above or below this the car seems to run fine. Any ideas as to what is causing this? Could it be something I did when replacing the starter? Any help would be much appreciated.

[maxhopper]

It's not the starter. Check for any wiring connections left unplugged or lines left loose.

[snipes1259]

I checked all the wiring connections and everything seemed to be like it was connected properly. The car has also begun to have a rough idle when in drive but not moving, like at a stop light or stop sign, but not while it is in park. It also has trouble accelerating after a stop sign with the whole car shaking. No check engine lights have appeared yet, but I'm keeping an eye out for them.

[NutriaforBreakfast]

try unplugging the mass airflow sensor connector
if it runs better it might be that
if it is that try cleaning it first with MAF cleaner
You may need to replace

[snipes1259]

I unplugged the MAF and it seemed to idle fine in drive. I plugged it back in and it drove fine for a bit but then after 20 minutes it started acting up again. Would cleaning or replacing the MAF fix this?

[NutriaforBreakfast]

Maybe or maybe not. I never have successfully cleaned one and
"brought it back to life" but others on the website have

Try cleaning it with MAF cleaner -You can get it at Walmart
Liberally spray the wire inside the hole
You might clean the connector with it too
Use a little silicone dialetric grease in the connector to make it
less susceptable to water intrusion after cleaning

You can also surf the threads in this website for more info
or the shop manual below;

http://www.nicoclub.com/FSM/I30/1998_I30/ec.pdf
On page EC115 there is a flowchart to diagonse MAF
if you have a multimeter you could check the power supply
on the connector and see if the ground wires are tight.

[snipes1259]

Well, yesterday I went out bought some MAF cleaner, cleaned the MAF and everything seemed fine. I went and drove it over to a friend's house and ran into no problems at all accelerating or while stopped at lights. The ride back last night was awful though. While driving home the car began to act very sluggish and a flashing CEL came on. I pulled over and restarted the engine and it wasn't flashing anymore, but the CEL was steady. I drove it pretty lightly the rest of the way and decided to look at the codes in the morning. I went out there this morning and checked them out and got both a knock sensor code and a cylinder 1 misfire code. The CEL was also flashing while I was still in park and the engine was started, but I unplugged the MAF and then replugged it in and it made it stop flashing. Do you guys still think it's the MAF that's causing all the problems?

[loystock]

Most likely the MAF sensor. From experience, you don't get a MAF trouble code until it's totally bad. Check the connectors (plugs and receptacles) and the MAF sensor itself for hairline cracks. The KS and misfire codes could have been caused by the failing MAF sensor.

[snipes1259]

Sorry for the late response, I've been overseas for a while and haven't had much time to work on the car. Anyways, I've replaced the MAF sensor and it definitely seems to have helped, but the issue still persists albeit not as often as before. Sometimes I'll start the car and it'll run perfectly and other times it will run like crap throwing the same codes as before. A buddy of mine described the acceleration of the car like someone learning to drive a manual. Any ideas as to what I can do to fix this?