sputtering under accel???
01-09-12, 07:18 AM
#1
sputtering under accel???
i posted a thread about this problem before but didnt get to much help so im posting again. so i drive a 91 N/A, when i try to accel and push the throttle down about halfway the car sputters and i begin to slow down, when it does this and i back off the throttle it gos back to normal. so i cant push my throttle down more then halfway. iv talked to a few people before about this and i have gotten everything from clogged fuel injectors to a ignition issue. any help much apprectiated.
01-09-12, 07:38 AM
#3
i can already check TPS and a clogged fuel filter off the list, i checked those as soon as i discoverd the problem. i just changed out my plugs and ignition wires to some brand new NGK iridium 8mm wires. could it be some sort of coil pack issue? i dont know alot about the eclectrical systems on cars so im not sure.
01-09-12, 12:39 PM
#4
Did checking for error codes yield any useful information? How about bypassing the Fuel Pump Relay. Done by disconnecting the plug to the relay and jumpering a Blue/Red wire to a Blue/Green wire. Relay is found under the air box and when acting improperly it can cause hesitations under strong acceleration.
01-09-12, 05:55 PM
#5
Did checking for error codes yield any useful information? How about bypassing the Fuel Pump Relay. Done by disconnecting the plug to the relay and jumpering a Blue/Red wire to a Blue/Green wire. Relay is found under the air box and when acting improperly it can cause hesitations under strong acceleration.
01-09-12, 06:06 PM
#6
Pulling codes or the relay? To bypass the relay is as easy as it appears. Unplug it and there will be a series of Blue/Red wires ( 3 of them) and a couple of Blue/Green wires in a single plug (six wires in all). Jumper one of the Blue/Red wires to one of the Blue/Green wires in the plug and the bypass is done. Plug also has a Green/Red wire (not used).
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01-10-12, 12:26 AM
#8
Full Member
I don't mean to piggyback your post or anything but I have a similar issue every now and then. When I come off the clutch and give it some gas it just bogs down and feels like it's gonna die until I let off the gas. Could you let me know what you find out because I haven't figured it out myself -_-
01-10-12, 03:24 AM
#9
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That's where I would start. I have seen a plugged cat do some funny stuff like that as well...
01-10-12, 09:25 AM
#13
Then your problem might be related to the secondary injectors as they come on line at 3800 rpm and under load which does not occur when reving in neutral. ECU pins 3F and 3H should have battery voltage w/key to on. If either doesn't then the injector plug is loose or one of the wires in the plug are pulled back. You also might have a hesitation problem caused by poor grounding of the ECU.
You can disconnect the TPS and unplug the vacuum hose to the Pressure Sensor and cap it and this will simulate load on the engine so as to get the secondaries to fire w/the engine rpm above 3800 w/the car in neutral (free reving). If it bogs/hesitates when doing this you can try jumpering a ground wire from an engine sensor ground and the other end of the jumper wire to a clean spot on the engine such as the thermostat housing. You'll need two people to do this. You can use the ground wire at the Pressure Sensor or TPS (Emission side of the harness which is what the TPS pigtail and Pressure Sensor plugs in to). The wire is Black (not Black/White).
You can disconnect the TPS and unplug the vacuum hose to the Pressure Sensor and cap it and this will simulate load on the engine so as to get the secondaries to fire w/the engine rpm above 3800 w/the car in neutral (free reving). If it bogs/hesitates when doing this you can try jumpering a ground wire from an engine sensor ground and the other end of the jumper wire to a clean spot on the engine such as the thermostat housing. You'll need two people to do this. You can use the ground wire at the Pressure Sensor or TPS (Emission side of the harness which is what the TPS pigtail and Pressure Sensor plugs in to). The wire is Black (not Black/White).
01-10-12, 10:46 AM
#14
Then your problem might be related to the secondary injectors as they come on line at 3800 rpm and under load which does not occur when reving in neutral. ECU pins 3F and 3H should have battery voltage w/key to on. If either doesn't then the injector plug is loose or one of the wires in the plug are pulled back. You also might have a hesitation problem caused by poor grounding of the ECU.
You can disconnect the TPS and unplug the vacuum hose to the Pressure Sensor and cap it and this will simulate load on the engine so as to get the secondaries to fire w/the engine rpm above 3800 w/the car in neutral (free reving). If it bogs/hesitates when doing this you can try jumpering a ground wire from an engine sensor ground and the other end of the jumper wire to a clean spot on the engine such as the thermostat housing. You'll need two people to do this. You can use the ground wire at the Pressure Sensor or TPS (Emission side of the harness which is what the TPS pigtail and Pressure Sensor plugs in to). The wire is Black (not Black/White).
You can disconnect the TPS and unplug the vacuum hose to the Pressure Sensor and cap it and this will simulate load on the engine so as to get the secondaries to fire w/the engine rpm above 3800 w/the car in neutral (free reving). If it bogs/hesitates when doing this you can try jumpering a ground wire from an engine sensor ground and the other end of the jumper wire to a clean spot on the engine such as the thermostat housing. You'll need two people to do this. You can use the ground wire at the Pressure Sensor or TPS (Emission side of the harness which is what the TPS pigtail and Pressure Sensor plugs in to). The wire is Black (not Black/White).
01-10-12, 10:56 AM
#16
dang, oh well, looks like i gotta man up and try to do this without someone holding my hand haha but ill try disconnecting the TPS and unpluging the vacuum hose to the Pressure Sensor and all that jazz later today. ill see if my secondaries fire up or not. ill also go through and clean all my grounds up and make sure everything is good on that end.
01-10-12, 11:09 AM
#17
The grounds to focus on would be related to the ECU as opposed to the charging circuit. If the car stutters after you remove this and cap that then one of the things to check would be the grounds for the ECU besides the condition of the secondary injector plugs.
01-12-12, 10:55 AM
#23
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the S5 ( 89 to 91) used a different system than the S4 (86-88) many people mistakenly have removed the air pump which is needed to actuate the 5th and 6th ports .. without it the engine falls flat at around 4500 rpm ..sometimes the 5th and 6th port get stuck from not revving to redline ...allot in automatics ..these can be checked with a low pressure hose to see them work. Download a service manual at this link to get the picture
http://wright-here.net/cars/rx7/89_manual.htm
http://wright-here.net/cars/rx7/89_manual.htm
01-12-12, 11:12 AM
#24
the S5 ( 89 to 91) used a different system than the S4 (86-88) many people mistakenly have removed the air pump which is needed to actuate the 5th and 6th ports .. without it the engine falls flat at around 4500 rpm ..sometimes the 5th and 6th port get stuck from not revving to redline ...allot in automatics ..these can be checked with a low pressure hose to see them work. Download a service manual at this link to get the picture
http://wright-here.net/cars/rx7/89_manual.htm
http://wright-here.net/cars/rx7/89_manual.htm
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