I have a 98 lx, that someone did a manifold swap on (manifold doesn't have an IACV) d15 maybe?, idk all what they did, but it runs. The problem I have is cold starts. The car fires up fine, runs smooth for maybe 5-10 seconds, then the idle dumps down really low, the car sputters and bucks for the next 20 seconds or so, then everything goes back to normal and the car will drive fine all day.
When cold you can just let the car idle, it wont stall, but the rpms will get really low, so low idk how it doesn't stall. Or you can try to drive it, but when you try that, the car just losses all power almost like its turned off, if you stay on the peddle it will almost like, pop pop, then buck forward at full power for a split second, and go back to popping and sputtering.
The main problem here is the car has to be cold, as in sitting for 3 hours or so, and the problem only last for 30sec to 1min when it happens, if it happens (happens more often then not though). Which makes testing a b***h. The only code it has is a cat code.. The past owner removed that.. The cap was pretty dirty (cleaned the carbon tracking) and the post are kind of burnt up, the rotor is pretty shitty, plugs IDK how old, wires are super long but test OK. I actually put another set of injectors in I had to see if that was the issue. Doesn't appear to have a thermostat (just picked one up), only has 1 O2, TB was cleaned, it has the IAC that is on the bottom of the TB, it's clean and moves. However I don't want to think its any of that stuff since the car drives perfect after its made it past that cold start operation.
I don't really know where to go from here, mostly since its such a limited window for the problem, and such a long wait between windows. The car makes good power, once you get on it, I drive it hard. With a real wideban on it, its pretty spot on even for open loop. I found a few really old post before posting this where a few people had a problem some what close. 1-2 of them say the ECT sensor was the problem, but most every post went unanswered besides check plugs, clean the IAC ect type stuff. All of them claimed to do every basic thing under the sun, cap/rotor/wires/plugs/air filter ect.
So if anyone has any ideas..
Thanks
When cold you can just let the car idle, it wont stall, but the rpms will get really low, so low idk how it doesn't stall. Or you can try to drive it, but when you try that, the car just losses all power almost like its turned off, if you stay on the peddle it will almost like, pop pop, then buck forward at full power for a split second, and go back to popping and sputtering.
The main problem here is the car has to be cold, as in sitting for 3 hours or so, and the problem only last for 30sec to 1min when it happens, if it happens (happens more often then not though). Which makes testing a b***h. The only code it has is a cat code.. The past owner removed that.. The cap was pretty dirty (cleaned the carbon tracking) and the post are kind of burnt up, the rotor is pretty shitty, plugs IDK how old, wires are super long but test OK. I actually put another set of injectors in I had to see if that was the issue. Doesn't appear to have a thermostat (just picked one up), only has 1 O2, TB was cleaned, it has the IAC that is on the bottom of the TB, it's clean and moves. However I don't want to think its any of that stuff since the car drives perfect after its made it past that cold start operation.
I don't really know where to go from here, mostly since its such a limited window for the problem, and such a long wait between windows. The car makes good power, once you get on it, I drive it hard. With a real wideban on it, its pretty spot on even for open loop. I found a few really old post before posting this where a few people had a problem some what close. 1-2 of them say the ECT sensor was the problem, but most every post went unanswered besides check plugs, clean the IAC ect type stuff. All of them claimed to do every basic thing under the sun, cap/rotor/wires/plugs/air filter ect.
So if anyone has any ideas..
Thanks
