1998 Chimaera 450 Misfire after minor job
Discussion
blitzracing said:
It does look low, but not low enough to stop the engine running.
Back to basics. Try starting with some Easy start into the AFM intake and see if it will fire. This will at least isolate of its fuel or ignition. mind you the fact we get an AFM reading at all on cranking means you have a spark interrupt at the coil so that bits good.
I have tried pouring about 200ml of petrol into the plenum intake and that made no difference. I havent seen easy start for sale here before but probably its just because I've never looked. I just found it though Back to basics. Try starting with some Easy start into the AFM intake and see if it will fire. This will at least isolate of its fuel or ignition. mind you the fact we get an AFM reading at all on cranking means you have a spark interrupt at the coil so that bits good.
Edited by blitzracing on Tuesday 28th November 10:59
https://www.supercheapauto.co.nz/p/nulon-nulon-sta...
Must be an Aussie product
Hi guys, this is just a short reply as I’m heading out the door for dinner. I’m 95 % certain we’ve cracked it.
I grabbed some easy start and took the plugs out to check they were clean and dry. I used a small gas soldering burner to burn off any residue, then cleaned the plugs. My garage is a shared space in an apartment building so I waited till nobody was around before using the easy start. It was a bit busy today so to pad time out I decided to check the fuel pump. When I looked at the spade connectors they were covered in dry powder and oxidised. I cleaned them up.
When I tried to start the car, it misfired but ran. Using my temperature gun, I could see two cylinders weren’t firing. I swapped the leads out and tried again and away she went!!!
I checked the timing and that smoothed it out more.
It’s feeling really positive but I’ve not been for a road test yet as I’ve ran out of time. I’ll update again tomorrow.
I’m so happy that the engine is running again, I can’t quite believing it after all this time.
Thanks to everyone who has contributed, every comment has helped in one way or another. I honestly can’t thank everyone enough.
With great respect,
Steve
I grabbed some easy start and took the plugs out to check they were clean and dry. I used a small gas soldering burner to burn off any residue, then cleaned the plugs. My garage is a shared space in an apartment building so I waited till nobody was around before using the easy start. It was a bit busy today so to pad time out I decided to check the fuel pump. When I looked at the spade connectors they were covered in dry powder and oxidised. I cleaned them up.
When I tried to start the car, it misfired but ran. Using my temperature gun, I could see two cylinders weren’t firing. I swapped the leads out and tried again and away she went!!!
I checked the timing and that smoothed it out more.
It’s feeling really positive but I’ve not been for a road test yet as I’ve ran out of time. I’ll update again tomorrow.
I’m so happy that the engine is running again, I can’t quite believing it after all this time.
Thanks to everyone who has contributed, every comment has helped in one way or another. I honestly can’t thank everyone enough.
With great respect,
Steve
fingers crossed.
The fuel pump circuit is a bit ropey on these, multiple connection points that can corrode giving problems, also the filter gets overlooked because of its location.
May pay you to to renew the cable connectors at the pump as these corrode internally too.
Belt and braces is to rewire the pump with continuous cables from up front but this is a bit fiddly.
The fuel pump circuit is a bit ropey on these, multiple connection points that can corrode giving problems, also the filter gets overlooked because of its location.
May pay you to to renew the cable connectors at the pump as these corrode internally too.
Belt and braces is to rewire the pump with continuous cables from up front but this is a bit fiddly.
Belle427 said:
fingers crossed.
The fuel pump circuit is a bit ropey on these, multiple connection points that can corrode giving problems, also the filter gets overlooked because of its location.
May pay you to to renew the cable connectors at the pump as these corrode internally too.
Belt and braces is to rewire the pump with continuous cables from up front but this is a bit fiddly.
Great advice, there are a few small things that I want to sort out on the car but for now I'm looking forward to getting the battery back in the box and bolted in and the ECU wiring all wrapped and tidied up again. The fuel pump circuit is a bit ropey on these, multiple connection points that can corrode giving problems, also the filter gets overlooked because of its location.
May pay you to to renew the cable connectors at the pump as these corrode internally too.
Belt and braces is to rewire the pump with continuous cables from up front but this is a bit fiddly.
I took the car for a short road test when I got home and its running very well. Completely happy now.
Once again, thanks to everyone that chipped in. There were a few people that said go back to basics, Air, Fuel, & Spark and that as it turned out was the best advice. There was a while there that I couldn't see the wood for the trees. I had read several topics re fuel pressure and it I hadn't focused on that because initially I didn't have a pressure gouge. I was also not looking forwarded to connecting in a gauge either, simply because I live in an apartment and the garage is a shared space.
At the moment I'm running with the original plugs and the standard in line extenders. Assuming all goes well over the next copula of runs, I'll swap these out for the BPR7s and the lava shields.
Cheers guys, I'm looking forward to getting some k's under my belt
Once again, thanks to everyone that chipped in. There were a few people that said go back to basics, Air, Fuel, & Spark and that as it turned out was the best advice. There was a while there that I couldn't see the wood for the trees. I had read several topics re fuel pressure and it I hadn't focused on that because initially I didn't have a pressure gouge. I was also not looking forwarded to connecting in a gauge either, simply because I live in an apartment and the garage is a shared space.
At the moment I'm running with the original plugs and the standard in line extenders. Assuming all goes well over the next copula of runs, I'll swap these out for the BPR7s and the lava shields.
Cheers guys, I'm looking forward to getting some k's under my belt
d" was spot on really, on every level.
blitzracing said:
Drop the plugs out and let the whole lot dry out then. Easy to flood the engines and they over fuel when cold anyway so cranking makes it worse.
Thanks for all your help Mark. Your expert knowledge is so valuable I recon you should bottle it Cheers till the next time
Belle427 said:
Its not easy trying to diagnose stuff over the internet and sometimes it pays to take a step back and verify the basics.
Still cant quite grasp why those connections would be responsible if the pump ran but id guess there was a voltage drop/cutting out you were not able to hear.
I agree and when time permits I’ll go back through the checks that I’ve run before, including the fuel pressure.Still cant quite grasp why those connections would be responsible if the pump ran but id guess there was a voltage drop/cutting out you were not able to hear.
There is massive over capacity in the pump at idle and 90 percent of the fuel simply goes back to the tank so pressure control is the function of the regulator unless the pump is really below par. Loss of fuel pressure happens as engine demand goes up but it's really hard to measure on the road as you can Imagen. Regulator failure is rare but you can drop it off and put an airline on the input and see when it opens as you wind the pressure up. Loss of fuel pressure causes a drop in performance followed ultimately by a mis fire under heavy load.
What a read!
Such a happy ending, and great to see a thread come full circle.
So just to conclude, you had weak fuel pressure due to corroded fuel pump connections? Was this not apparent when you tested the fuel pressure? I think you did mention somewhere in the thread that your fuel pressure results were slightly low?
Such a happy ending, and great to see a thread come full circle.
So just to conclude, you had weak fuel pressure due to corroded fuel pump connections? Was this not apparent when you tested the fuel pressure? I think you did mention somewhere in the thread that your fuel pressure results were slightly low?
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