'94 3.5 hot start prob
CobraCDN
07-12-2006, 09:03 PM
Hi folks.
I've had a hot start prob ever since I changed injectors. After sitting for about a half hour it takes quite a bit of turning over before it fires up run rough for a ferw short seconds then runs good.. A buddy lent me a fuel pressure test kit, and I am losing pressure fast after engine shut down.. from 43psi to nothing in about 20 to 25 minutes. Fuel regulator past the test.. and there are no visible leaks from fuel lines, rail or filter. My main prob in diagnosing now is how to tell which injector or injector seal is to blame. I've been trying dissconecting 1 plug wire at a time thinking that if I have the incorrect one it will run twice as bad as it does not for the 1st few seconds after the hot start.
Fuel milege also got worse very recently... not sure if it is related to this, we were getting codes so I'll summerize:
mil 14 = Map sensor we replaced it and found a bad connection in a plug.
mil 51 = lean burn O2 sensors seem to test out fine with the voltameter, we just replaced the Map sensor so it is not that (We tested the New Map sensor also, along with the wiring & connections) So we cut off the catyletic converter (miss-spelled sorry). Mileage did improve some but not back to what it was at.
So perhaps and O2 sensor? And is there an easier way to test out which cylinder is flooding on the hot start.
Cheers
I've had a hot start prob ever since I changed injectors. After sitting for about a half hour it takes quite a bit of turning over before it fires up run rough for a ferw short seconds then runs good.. A buddy lent me a fuel pressure test kit, and I am losing pressure fast after engine shut down.. from 43psi to nothing in about 20 to 25 minutes. Fuel regulator past the test.. and there are no visible leaks from fuel lines, rail or filter. My main prob in diagnosing now is how to tell which injector or injector seal is to blame. I've been trying dissconecting 1 plug wire at a time thinking that if I have the incorrect one it will run twice as bad as it does not for the 1st few seconds after the hot start.
Fuel milege also got worse very recently... not sure if it is related to this, we were getting codes so I'll summerize:
mil 14 = Map sensor we replaced it and found a bad connection in a plug.
mil 51 = lean burn O2 sensors seem to test out fine with the voltameter, we just replaced the Map sensor so it is not that (We tested the New Map sensor also, along with the wiring & connections) So we cut off the catyletic converter (miss-spelled sorry). Mileage did improve some but not back to what it was at.
So perhaps and O2 sensor? And is there an easier way to test out which cylinder is flooding on the hot start.
Cheers
CobraCDN
07-18-2006, 07:17 AM
Well we pressure tested the injectors with the Fuel rails off the manifold.. I'll posta pic showiing how we did that :) . Found one leeting some fuel by and replaced it. I think we got that solved. Changed Idle air Control, and bought oxygen sensors.. i just need to get a wrench now to puill the old ones and install these. Last night we took it for a ride.. after about 80Kms (50 miles) check engine light came on (It alwats seems to come on about that time. arrrrg. Still getting 51 (Lean Burn) and now 23,24,27.... like a plug is lose again lol Though you would think the timing of it would not always be about the same.
Hey where is freaknasty????
Cheers
Hey where is freaknasty????
Cheers
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