Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
Hi. Im working on 2007 mazda cx7 turbo 2.3L motor. System
Problelem is First time start it will not idle up and it act alot like misfiring I have to hold the idle at high speed. when I crank the engine have reve it up and it actually misfires a lot and try to keep it above 2000 Rmp if i let it go it dies. I have to restart many times again and try to keep tying at high idle for 5 minutes until worm up and then it's fine.
How many miles are on this CX-7? Since these are direct injected, my first thought it severe carbon buildup on the backs of the intake valves. It happens to all DI engines, and will cause poor idle symptoms like this. Some times, it comes down to removing the intake for a visual on the intake ports themselves.
A leaking head gasket is possible, but that usually clears up much sooner than five minutes. Are you seeing any coolant loss or overheating?
Hi. Thanks. For reply. No engine code. Miles 190k. Runs drive no coolant leak or loosing no head gasket leak very nice drive pick up drive great.
I talked to someone on line justawnser about a months ago.one of technical told me disconnect the up stream band 1 sensor disconnect the battery terminal and reconnect then drive it. So I did what as he said. Did not make any difference. One of my worker found on line post similar symptoms and it was advised the this cold start relearn computer program problem and only deal can do it.
So. I have the snap on solus ultra scanner I have take live ready but I'm not good at it to understand what supposed to the actual numbers should be.
So i found you guys on line i normally get resolved. I have watched your videos and i order new mass air flow sensor and map sensor also I have replaced those yet. Thanx for your help.
So. I have the snap on solus ultra scanner I have take live ready but I'm not good at it to understand what supposed to the actual numbers should be.
Nice! Did you happen to save the data during the cold start issue? If you did, please e-mail it to me at wrenchturnsyou@gmail.com. I'll be happy to take a look at it. :cheer: Unless we see a big fuel trim issue, I'd suspect that the MAF and MAP won't fix anything.
Has the throttle body been cleaned recently? It's possible that we're just dealing with a coked up throttle body.
Carbon build up really could be the cause of your problem as Tyler mentioned,esp with that high a milage...
Another thing to look for is a vacuum leak, most probably at the intake area. If you could smoke test it...
If not check it with propane or even water while starting the engine stone cold.
An expert is someone who knows each time more on each time less, until he finally knows absolutely everything about absolutely nothing.
i replaced the turbo on my 2008 cx7 and now have the same problem. new turbo, throttle body, plugs and clean mas euns great when warmed up but won't idle and pops when cold. open to any ideas 2008 cx7 96000 miles old turbo was leaking oil causing smoke plugs were black when changed car runs fine code reader says running lean at idle and random misfires that is why i changed plugs
i replaced the turbo on my 2008 cx7 and now have the same problem.
I'd want to start by watching short and long term trims, Loop status, upstream wideband, downstream O2, MAF, MAP, ECT, IAT and engine speed during the cold start rough idle, and during a test drive.
Forscan is a great tool if you don't have it already.
forscan.org/
How lean it's running, and when it runs lean, will give us good diagnostic direction.
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