Hey guys my em1 hasnt been running good and i though id hook it up to a scanner and see wut the sensors are doing. everything is fine with sensors but for ignition timing whenever on load or just as i shift and try to accelerate it bogs down and slowly pics up. The ignition timing actually drops down to like 0 and even -4 when it does it. it shoots back up to 30 as i gain power. now i know the computer could be retarding the timing becuause it sees something wrong somewhere . i was thinking replacing the coolant temp sensor becasue thats the only thing i havent replaced. ive seen other bogging threads but lead nowhere i hope with this timing info someone gets some ideas?

 

Check the spark at all four wires. When load and/or WOT cause bogging that goes away at higher RPM, that's usually a weak spark. It would be having trouble jumping the gap at low RPM when the spark is the weakest, and at WOT when compression is highest. You probably shouldn't pay attention to how the timing changes when the motor bogs down. If the engine starts dying, it is slowing down when it should be accelerating which throws the timing off. It shouldn't be the cause of the problem, just a symptom.

 

Yeah alright thats wut i though, the timing is just a symptom but ive already replaced the coil and igniter in it to see if that helps. and it runs like a champ for a bit but then goes to its usual ways. Wut else could casue weak spark. I think i might try a cap and rotor and go from there as i did them a year ago and the rotor doesnt look like its in the best shape its got a brown spot on the end of it on the little teeth from all the arcing to the cap bridges. I dont really know wut else to try after that though.

 

Grounds, cap, rotor, wires, plugs affect spark in addition to the coil and ICM. To test the spark, either buy a spark tester or:

First, warm the car up completely to normal operating temperature or as hot as your motor gets. Some ignition components are affected by heat and problems with those parts may not show up until the engine is hot. Disable the fuel injectors and get a new or known good spark plug. Set the gap of this plug to your vehicle's specifications and make sure it is clean afterward. Wear gloves (welding gloves work great), preferably with latex or nitrile gloves underneath, and remove a spark plug wire from its plug. Connect the good plug to the end of the wire and hold the plastic deep-well tube at the very tip of the wire end with the threads of the plug touching bare metal on the valve cover. Have an assistant crank the motor while you watch the spark, carefully keeping all body parts as far from the plug, motor and car body as possible. Different types of plugs have different colored sparks but usually a good spark is a thick, strong flow of bright pink or is at least bright. Little blue or pink "lightning bolts" indicate a weak ignition. Check all four wires. If the sparks at all of the wires are weak, try holding the threads of the plug against the battery negative post to see if the better ground makes a stronger spark. This will test your entire ignition.

You follow a similar procedure when using a spark tester. If the ignition checks out alright, check the MAP sensor signal voltage after the car has been warmed up to normal operating temperature since a vacuum leak can cause similar problems.

 

Alright i will try that. I just replaced the cap and rotor it was dirt cheap at 25 bones for both so i though id eliminate that posibility. When i had the cap and rotor off i did notice the slightest amount of play in the distributor shaft. not a whole lot but you can feel it, i guess i should adress that before it gets really bad. but as for the spark tester i can do that tommorow at work. ive read that the p2t ecu had some issues or w/e so i might try to find an obd1 ecu like a p30 and try it. Also about the map sensor, on my tester i can read it and it never drops or anything. the vacuum goes up with rpm and doesnt fluctuate. Do you think it could be the coolant temp sensor?

 

The voltage on the MAP sensor shouldn't drop, it would be too high at idle if there was a leak. At normal idle (~750) your MAP sensor should put out about .4-.7 volts. Lower is usually better. Have you noticed any problems with your temperature gauge?

 

Not really any problems, but it does take a while to heat up and it never goes directly in the middle just a little colder. when i bought the thing it never warmed up due to a t-stat other than that nothing with the temp needle. when i drove it today it seemed better but still not 100%. ill check the map sensor and go from there.

 

hey dude... were u able to get ur issue fixed....??

 

no man its not fixed, i havent got around to checking the map but i think its fine casue on my scanner it reads fine. are you having the same issue? I was driving my friends ls integra the other day, and it just makes me hate my car i wish it would just run already ive poured so much money into it.

 

So update..I tried reseting my ecu just for fun and it seemed to work, its been fine for now but im sure it will return, Can this mean that the ecu is no good?