Toyota MR2 Message Board - View Single Post - HELP! How do I / where can I find <insert FAQ here>?!?

blazinmr2 · 10-31-2005, 08:51 PM

There are several areas where most owners find themselves working on and replacing. Here is a list of many common problems found in the 91/92 Turbos.

Radio antenna: When the radio antenna fails to retract or deploy, it is usually because the plastic grooved cable inside the retractable antenna mast has become stripped. Toyota sells the antenna mast for $40 or so, and this can be fairly easy to replace.

Exhaust Manifold: In the 91/92 models the manifold can warp, causing an exhaust leak and reducing power and response. Often times the manifold warps because one of the seven studs has broken or one of the nuts and fallen off. Fixing this problem can be expensive, especially if you don't do the work yourself. Listen for a crackling noise when the engine is cold and you depress the throttle.

Ball Joints: The ball joints on the MR2 can last a long time (100k miles), however, if you notice a shaking in your steering wheel at speed and you know that the wheels are all balanced and the alignment proper, than the ball joints may need to be replaced. Toyota sells these at -$35/each.

Leather Seats: If the seats are taken very good care of they tend to crack, harden, and tear, especially in the T-top cars. If enough damage is done expect to need new leather. Expensive!

Bouncing Speedometer Needle: This is a common problem in the 91192 cars as they utilize a cable run system. Sometimes the plastic speedo cable gear wears out at the gearbox, needing to be replaced. Other times the cable itself will fray, and will need to be replaced.

CD Player Skipping: The CD portion of the 3-n-1 stereo can sometimes misplay, skip, or not play, but this can be fixed fairly easily if your are prepared to open up the stereo unit.

Frozen Emeraency Brake Cables: Overtime the emergency brake cables can freeze up because of trapped moisture inside the cable shroud. The offending cable should probably just be replaced. Toyota sells them for around $50 for the left and right side cables. Use caution in the wintertime when using you E-brake.

Water Temperature Gauge Fails: Actually, it is the gauge's sensor that typically fails. The sensor hooks up to the water elbow on the driver's side of the engine. Expect the sensor to run $30.

Engines:

Normally-Aspirated: 5S-FE (2.2L)

Turbo: 3S-GTE (2.OL)

The 5S-FE produced 130hp @ 5400rpm in 1991192, 135hp from 93 on.

The 3S-GTE was always rated at 200hp @ 6000rpm and 200 lb.-ft or torque
at 3200rpm according to Toyota.

In reality few 91/92 MR2 Turbo cars produced that much power in stock form.

The Turbo engine produced between 9-12psi in high boost mode. Boost can be limited by the to 7psi if the ECU detects conditions that could be dangerous to the engine. The ECU has a fuel cut that cuts boost if the manifold pressure exceeds 12psi. In reality, many owners have found that the boost cut does not engage until higher than 12psi.

Turbo

The stock turbocharger on the MKII is Toyota's CT-26. It is water and oil cooled. The turbo also has an internal wastegate. The turbo utilizes a small (possibly 40-trim) compressor wheel, and an equally sized impeller on the exhaust size. Most have found that the exhaust side ultimately limits the turbo's power capabilities, in that it is not efficient at higher boost. For this reason, owners increasing boost should not exceed 14-15psi with a stock turbo.

Upgraded stock turbos come in various compressor sizes. These include -46, -50, -54, and -60 trim compressors. Most MR2 owners do not recommend going over the -50 trim. The -46 trim is excellent for quick response, while the -50 trim may be the best for creating overall power. Most owners find that with an upgraded stock turbo, horsepower is limited to about 260 rear wheel horsepower (rwhp)_ With the stock turbo, rwhp is limited to about 220.

The ultimate way to upgrade your turbo is to go with an after-market turbo. The Greddy TD-06 is a favorite among many owners, while true ball-bearing turbos, such as the T-314, is the best way to go custom high-horsepower machines. The T-314 does require an external wastegate. The Greddy T-67 is another good big turbo, and includes all necessary hardware for installation, including a tubular exhaust manifold. Both Greddy turbos are problematic in that they do not allow the use of the stock primary catalytic converter. This is fine for owners who do not live in areas that require emissions tests, but the rest of us would have to utilize an aftermarket catalytic converter and hope it still meets regulations. HKS produces a TD-05 turbo kit for the MR2, which allows the use of the stock primary catalytic converter. The downfall here is that the turbo is slightly smaller than the Greddy TD-06, so overall power potential will be slightly lower, all things being equal.

Intercooler
The MR2 Turbo suffers from poor placement of the stock intercooler. The intercooler is fed by the passenger side air scoop, which limits airflow through the intercooler. This means that the intercooler is not going to be as efficient as a front-mount design. There are several options to upgrade the intercooler. The first and cheapest is to disconnect the intercooler fan temperature sensor on the engine lid. By disconnecting the sensor the intercooler fan goes into a fail-safe always-running mode. This will increase the time the intercooler takes to heat soak, however the stock fan does not pull enough air through the intercooler to prevent this condition.

Your next option is to upgrade the intercooler fan with one from an aftermarket company, such as SPAL. Using a 7.5" puller fan is place of the stock fan, power levels will remain more consistent over a wider temperature range. This setup is even better when a pusher fan is installed on the opposite side of the intercooler. With this pusher-puller fan setup sandwiching the intercooler, higher boost levels are better supported over a wide ambient temperature range. SPAL fans typically run $65 a fan.

Your next option is to install an aftermarket intercoolerwith a bigger core. Oversized intercoolers are available from Greddy, HKS, and several other companies. Fans should still be utilized to maximize performance.

Boost Control
As with most turbocharged cars, there are two ways to increase boost, electronically and manually. A manual boost controller is much less expensive, but generally doesn't allow for accurate, on-the-fly boost adjustment. There are two types: bleeder and ball-and-spring. The bleeder type utilizes a needle valve, and restricts the flow of pressurized air to the wastegate. This slows the reaction time of the wastegate, thus allowing for higher than normal boost levels.

10-31-2005, 08:51 PM	#12 (permalink)
blazinmr2 Resident guitar shredder Join Date: Oct 2005 Location: Pella, Ia Posts: 781 Thanks: 0 Thanked 3 Times in 2 Posts iTrader Rating: (0/0% )	There are several areas where most owners find themselves working on and replacing. Here is a list of many common problems found in the 91/92 Turbos. Radio antenna: When the radio antenna fails to retract or deploy, it is usually because the plastic grooved cable inside the retractable antenna mast has become stripped. Toyota sells the antenna mast for $40 or so, and this can be fairly easy to replace. Exhaust Manifold: In the 91/92 models the manifold can warp, causing an exhaust leak and reducing power and response. Often times the manifold warps because one of the seven studs has broken or one of the nuts and fallen off. Fixing this problem can be expensive, especially if you don't do the work yourself. Listen for a crackling noise when the engine is cold and you depress the throttle. Ball Joints: The ball joints on the MR2 can last a long time (100k miles), however, if you notice a shaking in your steering wheel at speed and you know that the wheels are all balanced and the alignment proper, than the ball joints may need to be replaced. Toyota sells these at -$35/each. Leather Seats: If the seats are taken very good care of they tend to crack, harden, and tear, especially in the T-top cars. If enough damage is done expect to need new leather. Expensive! Bouncing Speedometer Needle: This is a common problem in the 91192 cars as they utilize a cable run system. Sometimes the plastic speedo cable gear wears out at the gearbox, needing to be replaced. Other times the cable itself will fray, and will need to be replaced. CD Player Skipping: The CD portion of the 3-n-1 stereo can sometimes misplay, skip, or not play, but this can be fixed fairly easily if your are prepared to open up the stereo unit. Frozen Emeraency Brake Cables: Overtime the emergency brake cables can freeze up because of trapped moisture inside the cable shroud. The offending cable should probably just be replaced. Toyota sells them for around $50 for the left and right side cables. Use caution in the wintertime when using you E-brake. Water Temperature Gauge Fails: Actually, it is the gauge's sensor that typically fails. The sensor hooks up to the water elbow on the driver's side of the engine. Expect the sensor to run $30. Engines: Normally-Aspirated: 5S-FE (2.2L) Turbo: 3S-GTE (2.OL) The 5S-FE produced 130hp @ 5400rpm in 1991192, 135hp from 93 on. The 3S-GTE was always rated at 200hp @ 6000rpm and 200 lb.-ft or torque at 3200rpm according to Toyota. In reality few 91/92 MR2 Turbo cars produced that much power in stock form. The Turbo engine produced between 9-12psi in high boost mode. Boost can be limited by the to 7psi if the ECU detects conditions that could be dangerous to the engine. The ECU has a fuel cut that cuts boost if the manifold pressure exceeds 12psi. In reality, many owners have found that the boost cut does not engage until higher than 12psi. Turbo The stock turbocharger on the MKII is Toyota's CT-26. It is water and oil cooled. The turbo also has an internal wastegate. The turbo utilizes a small (possibly 40-trim) compressor wheel, and an equally sized impeller on the exhaust size. Most have found that the exhaust side ultimately limits the turbo's power capabilities, in that it is not efficient at higher boost. For this reason, owners increasing boost should not exceed 14-15psi with a stock turbo. Upgraded stock turbos come in various compressor sizes. These include -46, -50, -54, and -60 trim compressors. Most MR2 owners do not recommend going over the -50 trim. The -46 trim is excellent for quick response, while the -50 trim may be the best for creating overall power. Most owners find that with an upgraded stock turbo, horsepower is limited to about 260 rear wheel horsepower (rwhp)_ With the stock turbo, rwhp is limited to about 220. The ultimate way to upgrade your turbo is to go with an after-market turbo. The Greddy TD-06 is a favorite among many owners, while true ball-bearing turbos, such as the T-314, is the best way to go custom high-horsepower machines. The T-314 does require an external wastegate. The Greddy T-67 is another good big turbo, and includes all necessary hardware for installation, including a tubular exhaust manifold. Both Greddy turbos are problematic in that they do not allow the use of the stock primary catalytic converter. This is fine for owners who do not live in areas that require emissions tests, but the rest of us would have to utilize an aftermarket catalytic converter and hope it still meets regulations. HKS produces a TD-05 turbo kit for the MR2, which allows the use of the stock primary catalytic converter. The downfall here is that the turbo is slightly smaller than the Greddy TD-06, so overall power potential will be slightly lower, all things being equal. Intercooler The MR2 Turbo suffers from poor placement of the stock intercooler. The intercooler is fed by the passenger side air scoop, which limits airflow through the intercooler. This means that the intercooler is not going to be as efficient as a front-mount design. There are several options to upgrade the intercooler. The first and cheapest is to disconnect the intercooler fan temperature sensor on the engine lid. By disconnecting the sensor the intercooler fan goes into a fail-safe always-running mode. This will increase the time the intercooler takes to heat soak, however the stock fan does not pull enough air through the intercooler to prevent this condition. Your next option is to upgrade the intercooler fan with one from an aftermarket company, such as SPAL. Using a 7.5" puller fan is place of the stock fan, power levels will remain more consistent over a wider temperature range. This setup is even better when a pusher fan is installed on the opposite side of the intercooler. With this pusher-puller fan setup sandwiching the intercooler, higher boost levels are better supported over a wide ambient temperature range. SPAL fans typically run $65 a fan. Your next option is to install an aftermarket intercoolerwith a bigger core. Oversized intercoolers are available from Greddy, HKS, and several other companies. Fans should still be utilized to maximize performance. Boost Control As with most turbocharged cars, there are two ways to increase boost, electronically and manually. A manual boost controller is much less expensive, but generally doesn't allow for accurate, on-the-fly boost adjustment. There are two types: bleeder and ball-and-spring. The bleeder type utilizes a needle valve, and restricts the flow of pressurized air to the wastegate. This slows the reaction time of the wastegate, thus allowing for higher than normal boost levels.