Folks, need some insight.

I had a hesitation problem which forced me to replace my upper and lower intake manifold gaskets. While I was down there I installing new spark plugs; this was nearly 5 months ago. It solved my hesitation problem. However, after that half year I received a code for a bad fuel injector. Replaced fuel injector for cylinder 1 and all was well but that didn't last. Another month goes by and I get a bucket-full of codes:

p0301-Cylinder 1 misfire
p0303-Cylinder 3 misfire
p0305-Cylinder 5 misfire
p1316-misfire excess emission
p1111-CAT System Fault

I go on and clear the codes hoping to get less codes and a more accurate diagnostic. 2 days later the check engine light returns with :

p0301-Cylinder 1 misfire
p0303-Cylinder 3 misfire
p0305-Cylinder 5 misfire
p0174-System Too Lean Bank 2
p1316-misfire excess emission
p1000-On Board Diagnostic System Readiness Test Not Complete

1.) Is it possible my fuel injectors are bad or is it my ignition coils?

More info: while in idle my vehicle stutters but returns to normal when accelerating. Sometimes If i accelerate past 2900 RPM the engine loses power (makes me drive or shift before 3K RPM). Lets keep in mind this car has a nice 161K miles on it.

 

I ran into a similar scenario after getting a tune up. Kept getting a surge or lurch when stopped, or it would lose all power uphill and misfire. If I mashed on the gas it would power through though. Never got any codes at first and it went on for months until I eventually started getting some misfire codes and the car literally would bog down and choke if I gave it gas. I replaced the crankshaft sensor, IMT gaskets, MAF & MAP sensors to no avail. I ended up going back and replacing the plugs again, this time myself, and gaped them at .052 plus I did new plenum gaskets and new coils. Fixed everything, except one new coil was bad so I put an old one back on that wasn't bad. No misfire issues since.

Now I'm just tackling an annoying P2135 (Throttle/Pedal Position Sensor/Switch 'A'/'B' voltage Correlation) error. Seems simple and straight forward from the description but it's not turning out to be.....oy vey!

Hope this helps.

 

ugotmale,

Thanks for the info. I'll go ahead a change the ignition coils then. I'll reply with the results but since it's the holiday season don't expect to hold your breath. Luckily I have the wife's car to get to work

 

ugotmale,
on the pedal position sensor the easiest thing to try would be to pull the connector off the top of the PPS box and clean it with contact cleaner and see if that helps. The PPS is not that complex, it's just a couple of thin film carbon resistors and gold-plated brushes that slide across the resistors. There's not much that could go wrong except wearing out the carbon film or some type of oxidation or contamination.

 

Thanks sawduster. I'll get under the dash this weekend and check out the pedal - I assume the sensor is accessible from there. I've never actually looked for it. I'm also going to check the harness wire that plugs into the throttle. I looked it over briefly before and nothing looked frayed or damaged, but I want to take a deeper look at it.

 

Sorry for the delay but here is the result of all those codes:
After spending $ on fuel injectors and ignition coils the real problem was the breather hose. I can't stress enough how many times I checked that thing but never noticed it being cracked. I attached a picture for better view. By the way, the hose is ripped a lot more than when I discovered it the first time. So all codes have been removed and car drives without any problems.

 

You can obtain silicone hoses as direct replacements for these items. A much better long term bet.

 

I just cut the thing open and stuck a copper pipe right in the middle. It was a tight fit but didn't cost me a penny and works like new so now I can

 

tiny, I have a spare replacement ribbed hose I could send your way. I bought a replacement hose not realizing that the one already on the car was the new version to the type you still have. There's nothing wrong with it, i just swapped it out anyway instead of sending the one I bought back.