SF-FC3S

I got my 7 running fine now and she was making me happy until I noticed that the clock is reset everytime I get in the car, and she seems to not want to rev very high. I've read all about the 3800 rpm problem with the grounding issue and it seems that all my grounds are good and the ground battery terminal seems fine as well. I don't even know if the problems are related but please let me know.

SF-FC3S

seriously?

need RX7

iTrader: (4)

S4 or S5, n/a or TII?

RotaryRocket88

iTrader: (7)

Answer his questions ^. What does the power loss feel like? Hitting a wall at ~6000 RPM, or does it studder, then smooth out past it?

The clock is a POS, so don't worry about it. Bad solder joints in the warning light circuit board.

RotaryRocket88

iTrader: (7)

Here's another thread about a similar problem.:https://www.rx7club.com/2nd-generation-specific-1986-1992-17/power-drop-noticeable-hesitation-issue-high-6300-rpm-802779/

If yours reacts like this, chances are it's a lean spot killing power in a specific RPM range.

Molotovman

iTrader: (49)

How many Miles are on the car, you could have clogged cats. You also might want to adjust the TPS(Throttle Position Sensor). Use the search function, there are a lot of threads on those two topics already.

SF-FC3S

Its a 1988 turbo II. Its got about 100000 miles on the motor. I plan on replacing the exhaust as soon as I can afford it, but at the moment the thermostat and radiator are my biggest concerns. Could they cause the problem? It feels like at 6000 rpm the engine dramatically loses power. It continues to spin, but its almost like the turbo quits. Maybe that's the problem? Ill post a video later.

RotaryRocket88

iTrader: (7)

No, cooling issues don't cause power loss.

What boost is the engine making prior to 6000 RPM, and what pressure does it maintain past it? Stock should be about 5-6 psi steadily up to redline (7000 RPM).

My guess would be a mixture problem like in the thread I linked to. That's on a non-turbo, but a severe lean or rich condition can cause sudden power loss. On a rotary, and especially on turbo rotaries, lean conditions are bad news. Is the car modified in any way, and do you have a wideband 02 sensor/gauge or even a narrowband gauge?

SF-FC3S

I'm totally confused now. The reason I wanted to replace the thermostat and radiator is because when I drive it to work, the temp gauge makes its way up to up to pretty hot and I park and move on to pretending to write people tickets (like I give a **** about how fast you drive when I probably drive faster) in the Impala. If I try to start the 7 within like 2-3 hours of driving it, it won't start. Its still hot, and I have to leave it. So I've been taking it to work each day and it sits for my 10 hour shift then starts right up when its time to go home.

This morning my OEM thermostat got here so I installed her up all nice and such and drained all the coolant and put some nice new coolant in her. Guess what? For some crazy reason, all my power is back up to my redline, but she's still overheating. I'm confused. It has a Koyo water pump on it from the looks of it but besides that its bone stock. Also I just found out the cluster was replaced. The engine was rebuilt 40k ago and the original cluster says 182k miles. I have no idea if the motor is a new one or the original.

If the problem is that engine is old and screwed let me know so I can try to find where to get a newer rebuilt one. I'm gonna go with the rotary shacks t5 ford mustang tranny conversion cause getting it into 2nd is a bitch. I'm on my phone so I'll get some instant messenger set up to use. Probably AIM under the name sffc3s. Tango.

SF-FC3S

I'm totally confused now. The reason I wanted to replace the thermostat and radiator is because when I drive it to work, the temp gauge makes its way up to up to pretty hot and I park and move on to pretending to write people tickets (like I give a **** about how fast you drive when I probably drive faster) in the Impala. If I try to start the 7 within like 2-3 hours of driving it, it won't start. Its still hot, and I have to leave it. So I've been taking it to work each day and it sits for my 10 hour shift then starts right up when its time to go home.

This morning my OEM thermostat got here so I installed her up all nice and such and drained all the coolant and put some nice new coolant in her. Guess what? For some crazy reason, all my power is back up to my redline, but she's still overheating. I'm confused. It has a Koyo water pump on it from the looks of it but besides that its bone stock. Also I just found out the cluster was replaced. The engine was rebuilt 40k ago and the original cluster says 182k miles. I have no idea if the motor is a new one or the original.

If the problem is that engine is old and screwed let me know so I can try to find where to get a newer rebuilt one. I'm gonna go with the rotary shacks t5 ford mustang tranny conversion cause getting it into 2nd is a bitch. I'm on my phone so I'll get some instant messenger set up to use. Probably AIM under the name sffc3s. Tango.

NeCr0mStR

iTrader: (3)

Hot start issues have been covered LOTS and LOTS on here. Do a search for hot start problems. This may help you more than you know.

RotaryRocket88

iTrader: (7)

Common hot-start problems. Dirty injectors & an overly rich start map cause this. The injectors can be professionally cleaned. And a fuel cut switch or pulling the EGI fuses, then cranking to flood clear can help too. The only true fix for it however, is with a programmable ECU (standalones, Rtek stage 2). But sometimes cleaning the injectors is enough. Search "hot start" or "flooding".

Something else changed. A thermostat wouldn't do anything other than affect maximum coolant temps. How high on the stock temp gauge does it get? Normal is 1/4 - 1/2 way up. You may have an old clogged radiator, bad water pump or something similar. On the more extreme side, you could have blown coolant seals that would cause bubbles in the coolant. Same symptoms as a blown head-gasket on a piston engine.

40,000 miles is hardly old, but it depends on how many new parts were used in the build, and whether any questionable parts were re-used.

NeCr0mStR

iTrader: (3)

If you are not sure about the cooling being clogged either get one of the inline hose adapters for the heater core and try flushing it yourself. If you don't feel confident in doing this take it to a proper cooling place, NOT a Valvoline or jiffy lube or something to that effect and have it all flow tested and cleaned. Also I don't know if this would cause a significant cooling problem but make sure that your oil cooler is flowing properly and that you have good oil pressure. There is a cooler for oil for a reason and if that is not doing the job it should it could cause the radiator to have to work double time to cool both the oil and the coolant. I don't know this for sure but it would make sense or the oil cooler wouldn't be there.

When it comes to the injectors leaking, that could be the injectors or the o-rings, or grommets letting fuel past and seeping into the engine when the car is sitting, essentially flooding it without you knowing it. Best thing to do in that situation is to have the injectors cleaned and balanced and replace all the o-ring's that are involved with the the fuel system. This means air bleed socket o-ring's and all, including the grommets just to ensure that they are sealing proper and there is no real chance of them being a problem later. My philosophy is that if you have it apart, replace all the little things so they don't bite you in the *** later.

SF-FC3S

Alright to answer all these questions. I do seem like I burn through a tank of gas pretty quick. And the stock temp gauge gets at about 3/4 when I'm being nice and gets about an eighth an inch away from the H when I kick her ***. The radiator does seem hot as ***** on one side and ok on the other side. The water pump is the only shiny thing in the engine bay. Seems like a new koyo was put in recently. Id like to put a power fc in her at some point but that some serious green for E-3 pay at the moment. If its runnin too rich how can I fix that cheaply?

I was super confused about the thermostat power change too cause that makes no sense. There was a wire connected to something under the motor that I thought was disconnected, so I pulled it and zip tied it to the frame. Lol.

NeCr0mStR

iTrader: (3)

The only way to lean it out if its rich is to get it back to factory new essentially and than it still runs rich naturally. You would need to do an engine management system for the other option. What kinda MPG do you get? Check that and this will tell you how rich it is. Best thing to do to safeguard from running hot is to put in an aftermarket water temp gauge.

SF-FC3S

So does everyone use this rtek? Or is the Apexi Power FC a viable option. I'm no mechanic yet, so I need something fairly simple and stable and I've heard so many horror stories about the piggyback ecu's.

RotaryRocket88

iTrader: (7)

3/4 to 7/8 or so is way too hot. That's in the 220 - 230*F range. The stock S4 gauge is pretty good, while the stock S5 one sucks, so you can be fairly sure it's accurate. To put it in perspective, the thermostat cracks open at 183*F, so your system is allowing it to continue heating far past that point.

Rteks are re-chipped stock ECUs not piggybacks. The stage 1 versions are tuned to be used with larger injectors, but are not user adjustable. The stage 2 versions are almost a standalone ECU, since they allow fuel/timing tuning, data logging, start fuel map adjustment, etc... Take a look at http://www.pocketlogger.com/index.php?pid=rtek7 for details. They range from $120 to $449.

But first, you should settle this overheating problem. Pushing those kinds of temperatures is bordering on damaging the engine. The radiator or even the stock clutch fan could be the cause. The fan is supposed to free-wheel at low temps, but then the clutch locks up as the radiator heats up. If it's not locking up, it's pulling virtually no air through the radiator.

SF-FC3S

I figured it was the radiator. I'll have to hit the hobby shop and try to flush the radiator until I can buy that godspeedproject one I've been eyeing.