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-   -   No start, stumping me. (https://www.rx7club.com/new-member-rx-7-technical-256/no-start-stumping-me-1063080/)

Rags 05-04-14 02:16 PM

No start, stumping me.
 
Hey fellahs, the rx7 has been running amazing ever since I had the motor rebuilt by bdc. So I moved back to Colorado a few days ago. I had the rx8 trailered, and I drove the rx7. While driving home she seemed to studder a little bit under partial throttle while at low rpms. Under mid-high rpms she was fine, as well as under boost, no problems. Well I made it all the way home and I parked the car over night. When I went out to start the car the next morning it took a few cranks to get her going, which Is normal when its 5 Celsius outside. I then drove it about 60 more miles, stopping 3 times along the way. Every stop she got harder and harder to start, taking about 10-20 cranks to get her to go. She ran fine other than the studder at low rpms which was still present. I went back home, turned the car off, waited overnight, then tried to start it the next day. She starts up one time. In this one time she sounded like a lawn mower, she would rev up but not stay idling. I've blown the engine in both of my rotaries, and I know that's not a good sound, it sounded just like the rx8 did when it blew, but it didn't sound like the rx7 when it blew. I don't believe I have a blown motor. I pulled the plugs and they smelled heavily of fuel. I had just replaced the plugs about 1000 miles ealier with ngk 9's. I cleaned off the plugs on a wire wheel, there was no deposits or discoloring, they looked new still, other than being soaked. I pulled the fuse, and turned over the motor till she stopped spraying fuel out. I then pulled the wires off, and checked them. They looked new, but my oil cap had came off at an earlier date, and spilled oil down the side into the wires, so they were covered in oil. I took them out and cleaned them. Like I said, they look new, but I have only had the car 20,000 miles, and I don't know when they were changed before that, so I ordered new wires, they'll be here tomorrow. i reinstalled the wires for now. Next i pulled the fuel filter, which looked old as crap and was very plugged up compared to the new one. It still flowed, just not as well. after all this i tried to crank the car again. I turned it over a LOT. It just keeps cranking and spuddering, trying to catch, but not ever starting. I thought she just needed a good jump, so we tried to tow start her. Nope, she revs up just fine, got her to about 2k rpms down the road, but she wont even try to start. couple back fires, but it wasn't even trying to start. Towed her back to the house, checked the TPS. Voltage is good. pulled the plugs, they were dry. turned it over to check for pulses, i don't have a compression tester, but i got even pulses. And the motor has 18,000 miles on the rebuild 1 year ago. Fuel injectors were tested with the engine rebuild. No leaking fluids, oil changes on time, never got the car over heated. So my mod list is twin turbos at 15psi, full non sequential delete, duel intakes, straight pipe 3" all the way, stock injectors, walburo 255 fuel pump, upgraded fmi, upgraded radiator (not sure which ones they are, but they are big) greddy air separator, power FC greddy profec b boost controller, apexi turbo timer. So anybody know anything else i can be checking for? I'm at a loss right now on what is wrong. I'm really thinking that the fuel pump took a dump, because i jumped the diagnostic box between f/p and group and the pump makes noise, but not as loud as it usually is. Thanks for your help fellahs!

misterstyx69 05-04-14 10:43 PM

You need to properly compression test the engine.
Sorry to say but an EAR is not a reliable tool that can verify GOOD compression.

I did a "ear" test on an engine..sounded "ok"..compression was 20...

Rags 05-05-14 12:25 PM

Ah forgot to say its a half bridge as well.

Rags 05-05-14 05:35 PM

Lawl, rear rotor is 90 on all faces, front rotor is reading 40 - 45. Fml looks like another rebuild.

lduley 05-05-14 05:42 PM


Originally Posted by Rags (Post 11731022)
Lawl, rear rotor is 90 on all faces, front rotor is reading 40 - 45. Fml looks like another rebuild.

Seems like with a tired engine you would notice it spinning over faster......but i'm probably wrong

Rags 05-05-14 06:50 PM

Gunna try the atf trick. I'll post the results tomorrow.

lduley 05-05-14 08:54 PM


Originally Posted by Rags (Post 11731057)
Gunna try the atf trick. I'll post the results tomorrow.

Don't have high hopes lol

misterstyx69 05-05-14 11:54 PM


Originally Posted by Rags (Post 11731057)
Gunna try the atf trick. I'll post the results tomorrow.

try the POT trick..
..puff,puff.....wah?..forgot what the hell I was doin!


(fixed..lol!)


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