Ok, this is a continuation of this thread https://www.fiero.nl/forum/Forum2/HTML/060503.html#lastpost

where my friend just replaced his intake seal on the #2 cylinder because it is not running. Here's a list of all the symptoms and information about the engine.

Symptoms: rough idle, loss of power.
When disconnect spark plug wires from distributor cap on running motor,
all make difference except # 2.
Spark plug on # 2 looks darker then all the other spark plugs. (the rest
of the sparkplugs look the same.)
Engine has a noise kind of like baring noisy alternator noise, but it's
not. (noise has been there for quite some time, don't know if it's
related to the problem in any way)

Engine had been rebuilt 3 years ago, but has been stored for 2.5, has
been in the car and running since summer ~3000 km on it.
The only parts that have not been replaced are cast iron parts,
distributor, wiring harness and some sensors.

1. Check spark: took sparkplugs out one by one, ground body, crank
motor, sparks good & same on all plugs.
Sparkplugs bosch platinum +4 (7 days old).
Wire is good (checked in all possible ways including replacement) Tailor
8mm
2. Check fuel: replaced injector with spare one, checked power on
connector.
3. Compression 160 on # 2 & #1. haven't checked other ones.
4. There was a little oil on sparkplug so I've replaced valve seal on
intake valve. I think made a little difference for short period of idle
while lifters were adjusting.
5. today I'm going to switch #1 & #2 injectors, incase my spare one was
bad.

None of the above made any difference.

While working on this discovered valve stem scratched (looks like
something that had been done during assembly. Intake valve rocker bolt
bent towards pushrod.

Any ideas?

Thanks...

At the injector remove the connector and plug it into a spare injector. Point the spare unjector at a towel and have someone start the car. If it sprays fuel, you have a good connector. Put that injector in and try it again. Sorry, in my mind I'm picturing one of our manifolds and you can do the above without taking it apart. Since you have compression and ignition, it has to be fuel related. Thus, I think you should eliminate the cable and connector as being the cause and do the test even though it will require pulling the manifold top. BTW; sometimes injector connectors can look fully seat when they're not. Make sure that it is.

quote Originally posted by Elenor84: Sparkplugs bosch platinum +4 (7 days old).

Well, theres one of your problems. Those are the worst plugs you could have possibly chosen and make just about everything run like complete crap. I cant stand bosch saying that thier +4s have "superior burn" and being the "best performance plug".......the 4 ground electrodes actually disrupt the flame front inside of the combustion chambers and cause an un-even burn, which potentially decreases HP.

Stick with AC Delco, platinum is crap.

Francis7 is right check that the injector is pluged in all the way. you will have to pull the fuel rail and the cold start injector to test the injectors for spray it is also a good idea to unplug the coil befor this test you don't want any loose sparkes around with spraying gas. I would be a little concened about the bent rocker bolt that is a sure sign of a bigger problem. there is a small chance the guide is to tight and the valve is not closeing all the way when the engine is running? you need to check the push rod also when you are in there replacing the bolt and rocker. Take the pushrod and roll it on a flat piece of glass. A window in your house workes best but can be hard to explane to the wife. If it is bent it will be easy to see.

quote Originally posted by AutoTech: Well, theres one of your problems. Those are the worst plugs you could have possibly chosen and make just about everything run like complete crap. I cant stand bosch saying that thier +4s have "superior burn" and being the "best performance plug".......the 4 ground electrodes actually disrupt the flame front inside of the combustion chambers and cause an un-even burn, which potentially decreases HP. Stick with AC Delco, platinum is crap.

These spark plugs work great, and they improved the performance of the engine. They are certainly not crap. Thanks for your opinion though. Keep it in mind.

Keith is right, sorry I forgot to tell you to pull the coil wire. To test the connector you don't have to pull the fuel, just plug it into a spare injector. Now if the spare injector sprays, then you should pull the rail to make sure the injector in the engine is also spraying.

Must have had too much on my mind when I last responded. You do have to pull the fuel rail to test for spray. To just test the cable and connector, you can simply pull the connector and plug it into an extra injector and then feel for the click when it's supposed to fire.

Check to see if the rocker arms for the bad cylinder are moving the same as a good cylinder. Based on your dark plug symptom it would appear that the intake valve is letting some fuel in the cylinder. Sounds to me like you have a round cam lobe or something is bent/broken not allowing the exhaust valve of that failing cylinder to open when it should.

------------------
Tim
Red 88 Formula Auto 2.8 100K+ Miles

Logic is a systematic method of coming to the wrong conclusion with confidence!

[This message has been edited by FrugalFiero (edited 03-10-2005).]

I would also recommend that you double check that the spark plug wires are going to the correct cylinder. Good luck.

quote Originally posted by Elenor84: These spark plugs work great, and they improved the performance of the engine. They are certainly not crap. Thanks for your opinion though. Keep it in mind.

Im sure you think that they improved the performance of your engine because they are +4's, they improved the engine because your old plugs were shot, you just needed new plugs. I promise you that if you use AC you will like them much better. For some reason Bosch in general does not work well in GM's, Nissans, Toyotas and Fords with my experience and talking with Master Techs with over 20yrs field experience. And it is not my opinoin - its facts.....check out these posts:

https://www.fiero.nl/forum/Forum2/HTML/060397.html
https://www.fiero.nl/forum/Archives/Archive-000001/HTML/20010924-2-008971.html
https://www.fiero.nl/forum/Forum2/HTML/059855.html

[This message has been edited by AutoTech (edited 03-10-2005).]

quote Originally posted by AutoTech: Im sure you think that they improved the performance of your engine because they are +4's, they improved the engine because your old plugs were shot, you just needed new plugs. I promise you that if you use AC you will like them much better. For some reason Bosch in general does not work well in GM's, Nissans, Toyotas and Fords with my experience and talking with Master Techs with over 20yrs field experience. And it is not my opinoin - its facts.....check out these posts: https://www.fiero.nl/forum/Forum2/HTML/060397.html https://www.fiero.nl/forum/Archives/Archive-000001/HTML/20010924-2-008971.html https://www.fiero.nl/forum/Forum2/HTML/059855.html

The original wires were not shot. They were brand new as well. NGK.