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Rx7 drives fine untill I go for boost and nothing engine bucks and has no power?
Hey guys
Recently got my rx7 started after sitting for a while it drives fine without hitting boost but as soon as its about to enter boost its bucks and drops all boost pressure. Car hits boost fine in neutral.
Car is running a microtech ecu, has a external wastegate.
Have chucked brand new plugs in and made sure all leads are sparking... cooler elbows all seem to be tight ...what else should I look for?
if it was a stock ECU, i'd say fuel cut, but since its not....
it could be a lot of things, if you can log data, it might help (i'm not sure what the Microtech can do)
if you need to just go an look at stuff, you might check fuel pressure
Stupid question. Sure the plugs wires are on the correct spark plug?
I only ask as I had a very similar issue after working on my car. Car started and drove out of boost fine, but hit a wall and wouldn’t do anything in boost. Turned out to be my leading coil was disconnected. Plugged in and was perfect. Again, stupid question. I mainly ask since I see the leading wires zip tied and doesn’t look like a new zip tie.
if it was a stock ECU, i'd say fuel cut, but since its not....
it could be a lot of things, if you can log data, it might help (i'm not sure what the Microtech can do)
if you need to just go an look at stuff, you might check fuel pressure
Dont have a data logger for the microtech unfortunately....fuel pressure sits just under 40psi at idle on the fuel reg and dips a bit when free revving in neutral. What numbers am I looking for roughly fuel pressure wise?
Stupid question. Sure the plugs wires are on the correct spark plug?
I only ask as I had a very similar issue after working on my car. Car started and drove out of boost fine, but hit a wall and wouldn’t do anything in boost. Turned out to be my leading coil was disconnected. Plugged in and was perfect. Again, stupid question. I mainly ask since I see the leading wires zip tied and doesn’t look like a new zip tie.
when I pulled the plugs some were wet and some were dry??... but I am pretty sure the leads haven't been touched since I parked it up last and i made sure to know wich one went where .....how do I know wich lead goes from where from scratch? Coz wbat your describing is spot on it hits a wall and bucks with no acceleration until I change gears and drive out of boost again.
when I pulled the plugs some were wet and some were dry??... but I am pretty sure the leads haven't been touched since I parked it up last and i made sure to know wich one went where .....how do I know wich lead goes from where from scratch? Coz wbat your describing is spot on it hits a wall and bucks with no acceleration until I change gears and drive out of boost again.
trailing plug is on top, Leading plug is on bottom.
1 is front rotor 2 is rear rotor
leading coil mounted by the headlight, leading coil should have l1 and l2 marked on them. I see you have some aftermarket trailing coils mounted by the firewall.
Always could be something else but should check this since it’s simple. Interesting to know which were wet and which were dry.
Have you tried a new set of plugs? Edit: just read you tried new plugs. When I have had issues with tuning a new map from scratch and too much fuel the plugs would get wet and that would give me issues. I learned to keep a set of dry plugs so I could swap them out. But that was more for starting it up from being flooded. Could still try swapping in the other pair when they dry out.
Last edited by DR_Knight; Feb 12, 2025 at 02:56 PM.
trailing plug is on top, Leading plug is on bottom.
1 is front rotor 2 is rear rotor
leading coil mounted by the headlight, leading coil should have l1 and l2 marked on them. I see you have some aftermarket trailing coils mounted by the firewall.
Always could be something else but should check this since it’s simple. Interesting to know which were wet and which were dry.
Have you tried a new set of plugs? Edit: just read you tried new plugs. When I have had issues with tuning a new map from scratch and too much fuel the plugs would get wet and that would give me issues. I learned to keep a set of dry plugs so I could swap them out. But that was more for starting it up from being flooded. Could still try swapping in the other pair when they dry out.
Im pretty sure the leads are in the right spot the trailing plugs from the aftermarket coils are on the top and have blue caps on them.
might be a monster vacuum leak...I might check the wastegate but not liking my chances as it should still hit some sort of boost even with a faulty wastegate...boost comes on at 2700 as soon as its hit 2700rpm it bucks and even if I flatten the pedal out of boost it will cough and splatter.
Pretty sure I have found the problem BLOCKED SECONDARY INJECTORS!!!
tested the secondarys with a circuit tester and they are super blocked unlike the primarys wich flow.
Pretty sure I have found the problem BLOCKED SECONDARY INJECTORS!!!
tested the secondarys with a circuit tester and they are super blocked unlike the primarys wich flow.
If it’s been a while since they’ve been cleaned and/or if the car sat for a while, it’s probably a good idea to send them out for testing, cleaning, retesting. While you’re in there. It’s good to know what they’re actually flowing vs what the manufacturer claimed, or just due to clogs.
I’ve used rc engineering, but they are somewhat local since they’re in Los Angeles and I’m in San Diego. Usually a 3 day turnaround for me.
Do you not have a o2 wideband sensor? I’ve had a clogged fuel filter which showed itself running lean and not adjusting when trying to add fuel into the map on my wideband, definitely saved me.
Last edited by DR_Knight; Feb 14, 2025 at 12:46 PM.
If it’s been a while since they’ve been cleaned and/or if the car sat for a while, it’s probably a good idea to send them out for testing, cleaning, retesting. While you’re in there. It’s good to know what they’re actually flowing vs what the manufacturer claimed, or just due to clogs.
I’ve used rc engineering, but they are somewhat local since they’re in Los Angeles and I’m in San Diego. Usually a 3 day turnaround for me.
Do you not have a o2 wideband sensor? I’ve had a clogged fuel filter which showed itself running lean and not adjusting when trying to add fuel into the map on my wideband, definitely saved me.
getting the injectors cleaned and tested tonight secondaries were fully blocked. Get them back tomorrow morning.
everything from the intank pump to the injectors has been replaced besides he fuel reg wich is still working fine.
I might look into gettinggetlittke dash for the microtech to keep an eye on things
