No power when you floor the gas pedal

[TomoHawk]

My engine started running so crappy since I put on the new fuel rail. I thought it was because I 'cleaned' the AFM, and the resistance strip is damaged. I just got a used AFM off eBay, and it didn't help, so I started reading everything. I read that if the timing is off, it'll run rich. So I got a timing light and put it on there.

Problem was I didn't see any marks. On U.S. engines the TDC mark is kind of deep so it's really easy to see it. When I put the light on MY car, I didn't see any marks within the timing pointers(the one bolted on the timing chain cover.)

So I pulled the coil wire and cranked the engine in little bits to find the mark. After about 15 minutes I gave up. I will have to take it to a service place to have some pros set the timing. Maybe they can clean up the crank pulley so I can check it myself later. Then I will see if the Nissan dealer has a guy that knows Zs, and can do something with it.

The last time I drove my 280Z, the engine just about stalled when you floor it (when the TPS kicks in to richen the fuelmixture.) Otherwise, there's no power, no accelleration. I didn't get check the spark plugs yet.

thx

[beandip]

If the trouble started right after you messed with the AFM and and you found a damaged part . Start there first . Why do you question the timing if you havent ''adjusted '' it before this ? As to the timing marks . Look at the pully below where the degree marks are. Clean off the pully and you will find the mark . You may need to scrape away some grease and or dirt , but it's there . Some times the compression of the cylinders will cause the engine to stop turning in the same place or nearly so , that maybe why you are not finding the mark . If this is the case , remove the plugs and this wont happen .When you find it , Clean out the grove and paint with some white paint or some light color , chock will work . This way the mark will be easy to see with the timing light. These engines vary rarely will change timing all of a sudden unless there is a failure in the dist or something there is loose. Good luck with this . Gary

[TomoHawk]

Thanks Gary,

I was looking for the timing mark, but I didn't think about taking the plugs out. When I took the plugs out, there is a bit of oil dripping down from each spark plug hole, and they were well covered with soot. I think that last quart of oil I put in recently is blowing by the piston, interfering with the plugs, so there is an oil change coming tomorrow. I put in what is probably an extra quart because the dipstick is difficult to read, and it looked low on oil. No matter how carefully you put it in & pull it out, sometimes the oil slick goes half-way up the stick, or lower than the low mark, so I'm draining the engine, putting in exactly 5 qts, and we'll see if that helps mark the dipstick correctly.

I was going to mark the timing notch on the crank pulley with paint, but the engine was hot so I'll leave it for later when I can get it up on a lift and clean off the pulley rim. I don't really question the timing, as the engine was fine last summer except for the poor gas mileage. I'm checking the timing now because I've never done it on an L28 engine and it's not as easy as a V-8 with the fancy timing tape. I want to expose myself to all the parts of the Z car & engine, as I already know domestic cars, and the Bosch L-Jetronic fuel injection is new to me as well. So eventually I will know everything there is about the engine to keep it running & replace old stuff.

thx

[hls30.com]

I want to expose myself to all the parts of the Z car & engine,

thx

No wonder it isn't running-put some clothes on when you work on that car!!!

I just couldn't resist!! Seriously, I think you are on the right path now!

Will

[TomoHawk]

Oh. I thought you drove down my street & saw me with my shirt off. I get toots from the ladies sometimes.

86 & sunny in Ohio yesterday.

[DatsunZsRule]

Yeah, max should be about 4.5 quarts MAYBE a little extra. I bet a good thorough tune up will take care of a lot of your problems

Good luck man.

[TomoHawk]

I took out all the spark plugs and cleaned the soot off. I also put a bottle of engine cleaner into the gas tank. Cleaning the plugs helped a little. I also noticed (once) a little black smoke coming out of the muffler when I hammered the gas pedal around a corner.

thx

[DatsunZsRule]

Bottle of engine cleaner in the gas tank??? What did you use? :nervous:

If you want to clean out Carbon Buildup, Clean your intake valves, clean Catalytic, Converter ect. then I recommend using Sea Foam. to do the above, Start the engine. If cold, let it run so it warms up to normal. Remove the vacuum line at the brake booster, dump about 1/3 of the can down that vac. line. it will suck it into the intake. After you finish pouring 1/3 of the can into that vac. line, turn off engine. Let it sit turned OFF for about 5 minutes, then resecure vacuum line to brake booster. Then fire her up and rev her up good. You'll then put on a smoke show for the neighbors but it will only be briefly. After that, take her out on the highway and watch out for the piglets :laugh: do about 80 for a short time to help it do it's job. you will have to change plugs though after doing this. i did at least being that they got fauled but who cares. Plugs aren't that costly. After doing this, You'll feel like your driving a totally different car. After I did this, the car ran like I just drove it off the show room floor. This stuff is awesome. I'd try this since you haven't changed plugs yet. You only should have to do this procedure once as it cleans everything really good. You only have to do this to systems that have been neglected and are horribly carboned up

I'm positive you'll be amazed at the results. Good luck dude.

[TomoHawk]

I had my engine decarbonized last summer, but I might give it a go. I want to find a nice empty field out in the country to 'smoke it up.' In the 'burbs, you'll draw the P.D. and the Fire Dept. if anybody sees any smoke.

BTW, no catalytic converter on my car- not a California car.

thx

[DatsunZsRule]

Yeah, I thought about doing it somewhere else, then I thought, ahh the hell with it :laugh: It only last shortly. Plus my neighbors pretty much keep to themselves anyways which is a good thing

If you try it, post your results. It should help.

later.